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The 'Lost' September Callups: Nine Late-Season Stash Ideas For Deep Dynasty Leagues



Late in the 2019 season, MLB and the players’ union negotiated an end to unlimited September roster expansion. Rosters still expand in September, but only to 28 players.

As a result of the agreement, teams gained a 26th roster spot for the first five months of the season. From the owners’ perspective, their teams now save salary and preserve service time on many of the types of prospects who, under the old rules, would have received callups for the sixth and final month of the season.

It was customary under the old rules for MLB teams to call up top prospects coming off big seasons at the upper levels of the minors so that they could get their feet wet in a lower-pressure September environment. If the player will factor for the big league club next season, then call him up this September—or so the old line of thinking went.

This season, some top prospects affected by this change in how MLB teams operate include catcher M.J. Melendez and first baseman Nick Pratto, both of the Royals, as well as Reds righthander Hunter Greene and Twins third baseman Jose Miranda, the overall minor league leader for hits and total bases.

All of these top prospects performed at Triple-A and are no-brainers to be added to the 40-man roster in November, when their Rule 5 draft exemption period ends.

Melendez, Pratto, Greene and Miranda are prominent examples of the “lost” September callup, but they aren’t the only ones. There are a number of prospects who performed in Double-A and/or Triple-A this season and are almost certain to be added to their organization’s 40-man roster this November. In the past, these players probably would have seen big league time. Now, they are “lost” September callups.

Many of these players represent value potential in dynasty leagues. Below I outline nine such players to consider stashing in deeper formats. They may not become future fantasy stars, but with stakes this low, the potential benefit far outweighs the cost.

1. Jonathan Aranda, 1B/2B/3B, Rays

This season: 164 wRC+ ranks sixth in minors at 300 PA
Age next season: 24

Entering the season, Aranda had more experience in the winter Mexican Pacific League than he had above the Low-A level. But that changed in a hurry in 2021. Aranda quickly mashed his way out of High-A and shined at Double-A Montgomery, hitting .325/.410/.540 with 10 home runs in 79 games in the pitcher-friendliest league in affiliated baseball.

Aranda does many things scouts love. He takes competitive at-bats. He has a strong two-strike approach. He has surprising pull power. He finds the sweet spot frequently with his quick lefthanded swing. What scouts are less enamored of is Aranda’s defensive profile. His best position is first base, but at 5-foot-10 he doesn’t fit the prototype there. He could learn to fake it at second or third base as part of a multi-positional regular role. But his bat is not in question.

2. Juan Yepez, 1B/3B, Cardinals

This season: 154 wRC+ ranks 16th in minors at 300 PA
Age next season: 24

The Cardinals liked how Yepez, then a 17-year-old first baseman in the Braves’ system, had handled himself when he made his pro debut in 2015. He put up an .822 OPS as one of the youngest players in two different Rookie leagues. St. Louis had that in mind when it acquired him from Atlanta for Matt Adams in 2017.

Four years later, the Cardinals’ prescience and patience are paying off. Yepez has quietly climbed to Triple-A and hit .291/.381/.593 with 22 home runs in 91 games, putting up a .973 OPS that is fourth highest at the level among qualifiers. A refined batting eye ties the package together. Yepez is the rare player to hit for average and power—.306 isolated slugging—while maintaining a strikeout rate below 20%.

The universal DH could create playing time for Yepez in 2022, because he won’t budge Paul Goldschmidt or Nolan Arenado off the corners in St. Louis.

3. Jeremy Peña, SS, Astros

This season: 142 wRC+ in limited sample
Age next season: 24

While outfielders Jake Meyers and Bryan De La Cruz flourished at the Astros’ new Triple-A Sugar Land affiliate and subsequently made their MLB debuts, Peña was working behind the scenes to return from wrist surgery he had in April. When he made his Triple-A West debut on Aug. 28, he started 1-for-14 before catching fire and batting .347/.410/.716 with nine home runs in his next 24 games.

Peña has a strong defensive reputation and is the top internal candidate to replace Carlos Correa when the shortstop leaves as a free agent this offseason. That’s why Peña getting back on the field this season was imperative to Houston as it looks forward to 2022.

While Peña’s offensive outlook is less certain, he is coming off a rookie of the year performance in the Dominican League last winter and has hit for impact power this season, including in spring training when he homered off a 98 mph fastball from Jacob deGrom.

4. Steven Kwan, OF, Indians

This season: 153 wRC+ ranks 18th in minors at 300 PA
Age next season: 24

Kwan had a reputation as more of a slap hitter at Oregon State when Cleveland drafted him in the fifth round in 2018. He hit just three home runs in his first two pro seasons and then missed 2020 to the pandemic. But Kwan muscled up heading into 2021 and focused on making impact as much as contact. He also added a slight leg kick and learned to pull the ball more often.

Kwan homered seven times with Double-A Akron and has added five more in one month with Triple-A Columbus to quadruple his career total for homers. He has managed the feat while still retaining his fine batting eye—34 walks, 31 strikeouts—and a .402 on-base percentage.

Slowed by a hamstring injury this season, Kwan is more of an above-average runner than plus, but he is instinctual enough to see time in center field and perhaps reach double-digit steals. But as a 5-foot-9 outfielder without huge power, he will need to tread the Brett Gardner or Adam Eaton path to relevancy.

5. Tommy Romero, RHP, Rays

This season: 2.85 FIP ranks eighth in minors at 80 IP
Age next season: 24

The Mariners drafted Romero out of junior college in 2017. The Rays traded for him early in the 2018 season, sending Alex Colome and Denard Span to Seattle. Largely anonymous heading into 2021, Romero became more of a household name for pitching well at Double-A and Triple-A. In fact, his strikeout rate minus walk rate (26.2%) ranks sixth in the minors among pitchers with 100 innings. His 2.81 ERA ranks 10th.

Romero pitched effectively at High-A in 2019 but got a bit lost in the Tampa Bay organization’s immense prospect depth. That should no longer be considered the case. Romero has average or better stuff across the board, with the type of command of a four-pitch arsenal and deception to get the absolute most out of his stuff.

Romero could begin in a multi-inning bulk role for the Rays, but he has starter upside because he generates a lot of swings and misses with his 88-93 mph four-seam fastball up in the zone.

6. Cody Morris, RHP, Indians

This season: 2.16 FIP in limited sample
Age next season: 25

It seems like every college pitcher drafted by Cleveland in the top 10 rounds becomes a big league starter. Morris could be next in line. The 2018 seventh-rounder from South Carolina struck out 93, walked 20 and allowed three home runs in 61 innings this season, most of them at Triple-A Columbus.

Morris didn’t take the hill this year until July, after he recovered from a shoulder injury, but his results are notable because his strikeout, walk and home run rates translated to a 2.16 FIP that led all minor league pitchers with at least 60 innings. That Morris accomplished that in the upper minors and exclusively in a starting role—caveat: 74 pitches was his high mark—is impressive.

Morris pitches at 92-93 mph, reaches back for the high 90s on occasion, and gets a good amount of swing and miss. His changeup is his top secondary pitch, but he also gets chases on his breaking pitches. Morris has mid-rotation upside, perhaps better if he can stay healthy.

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7. Michael Stefanic, 2B/3B, Angels

This season: 137 wRC+ ranks 85th in minors at 300 PA
Age next season: 26

From undrafted to on the cusp of the big leagues, Stefanic has forced his way into the 40-man roster conversation with a big year. He hit .344/.419/.521 with 16 home runs through 101 games for Triple-A Salt Lake and ranked among the minor league leaders for hits and batting average.

Stefanic was not drafted in 2018 out of NAIA Westmont College in Santa Barbara, Calif. He latched on with the Angels after he sent a highlight reel to all 30 clubs. Four years later, he is barreling the ball consistently in the upper minors and not chasing out of the zone, showing many of the traits of a future big leaguer.

Where Stefanic fits defensively is a bigger question. He needs to add speed and range to stick at second base or arm strength to fit at third base.

8. Kyle Bradish, RHP, Orioles

This season: 3.48 FIP ranks 42nd in minors at 80 IP
Age next season: 25

The Angels drafted Bradish in the fourth round out of New Mexico State in 2018. He spent one season in the organization before being bundled to Baltimore along with three other pitchers for Dylan Bundy after the 2019 season.

Bradish quickly emerged as the best of the bunch. He didn’t allow a run in three Double-A starts this season to earn a quick promotion to Triple-A Norfolk, where he recorded a 4.41 ERA and 1.46 WHIP while striking out 99 in 81.2 innings.

Despite ordinary Triple-A numbers, Bradish has desirable fastball attributes. He ranges from 92-96 mph and touches 98 with extreme cutting action, all from a high arm slot. This gives him a larger margin for error when he misses his spot in the zone, and his fastball generates plenty of whiffs. Bradish’s secondaries require more work, but he has a feel for spinning his breaking pitches for chase pitches.

For some evaluators, Bradish is a No. 4 type of starter. For others, he’s a future closer candidate.

9. Diego Castillo, 2B/3B/SS, Pirates

This season: 129 wRC+ ranks 143rd in minors at 300 PA
Age next season: 24

Signed by the Yankees out of Venezuela in 2014, Castillo didn’t advance past High-A in five pro seasons prior to this year. But work he put in during the 2020 shutdown has dramatically increased his exit velocity without sacrificing much contact.

The Pirates took note when they traded for Castillo and Hoy Park in July, sending reliever Clay Holmes to New York. Neither player was likely to make the Yankees’ offseason 40-man roster, but they will have significantly more opportunity to make an impression and accrue statistics in Pittsburgh.

Castillo has done a good job becoming more selectively aggressive this season. His 19 home runs represent almost a five-fold improvement on past work, while his overall batting line of .278/.357/.489 in 102 games, mostly at Double-A, represents his best work across the board. Second base is Castillo’s best position, but he can float around other infield spots.

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