With a middle of the pack offense that ranks seventh in the AL in runs scored per game—and ahead of only the Rangers in the West—the Mariners today called up two of their finest and hardest-hitting prospects from Triple-A Tacoma. Catcher Jeff Clement and right fielder Wladimir Balentien should be available for tonight’s game in Cleveland.

In corresponding roster moves, Seattle designated for assignment outfielders Brad Wilkerson (.232/.348/.304) and Greg Norton (.438/.500/.563). Clement, the organization’s top prospect, figures to take at-bats away from DH Jose Vidro (.209/.270/.330) and could conceivably see time behind the plate in a rotation with Kenji Johjima, who last week signed a three-year, $24 million extension, and/or Jamie Burke.

Clement was batting .397/.535/.692 for Tacoma with eight doubles, five home runs and 20 RBIs in 23 games. He ranked fourth in the Pacific Coast League in average and second in on-base percentage, thanks to a 22-12 walk-strikeout ratio. Drafted third overall from Southern California in 2005 as a power-hitting, lefty-batting catcher, Clement has not disappointed as a pro, batting .276/.360/.459 in 883 minor league at-bats.

Hitting comes easy for the 24-year-old Clement, but he’s had to work to make himself playable at catcher. He struggles to get his feet to work for him while throwing, and this season he had caught four of 17 (24 percent) basestealers, a figure that is in line with his established norms.

Balentien’s game is all about power: He’s topped 20 home runs in each of the past three seasons and he has a cannon arm he’s used to consistently rank among his league’s leaders in outfield assists. The 23-year-old has worked hard to refine his approach at the plate, though, and he’s no longer the out-of-control batter who has compiled 160- and 140-whiff seasons. Balentien was batting .254/.329/.619 for the Rainiers, with the highlight of the season coming Sunday, when he connected for three home runs in a game.

Signed out of Curacao in 2000, Balentien will be the second player, after Wilkerson, to attempt to replace the right-field production lost when Jose Guillen signed with the Royals (and when Adam Jones was traded to the Orioles). He’s batted .273/.342/.522 with 110 home runs in 1,961 (domestic) minor league at-bats. 

A look at how Clement and Balentien have fared with Tacoma in 2007 and 2008. And keep in mind that Tacoma’s Cheney Stadium favors pitchers.

ISO Isolated Power (SLG – AVG). K% K / PA. BB% (BB – IBB) / PA.