Righthander Greg Reynolds and second baseman Jonathan Herrera, two of the Rockies’ more promising upper-level prospects, already have been called to the big leagues out of necessity. Now two more—third baseman Ian Stewart and corner outfielder Seth Smith—are getting their shot.

Stewart, 23, and Smith, 25, both made their big league debuts last September and both have starred for Triple-A Colorado Springs this season. They’re taking the roster spots of shortstop Clint Barmes and right fielder Brad Hawpe, who both were placed on the disabled list.

The Rockies have tried Stewart, their first-round pick (10th overall) in 2003, on an outfield corner and at second base at various points during the past two seasons, but he profiles better at third base, where he has above-average potential offensively and defensively. Rockies manager Clint Hurdle indicated that Stewart will primarily fill in at third base, at least in the short term.

Four times recognized by the Prospect Hot Sheet this season, Stewart has batted .281/.374/.614 with 12 home runs and 43 RBIs in 171 at-bats this season. His name litters the Pacific Coast League leaderboards, but, more impressively, he ranks fourth in the minors in RBIs, second in runs (43) and seventh in extra-base hits (27).

Smith delivered key hits late last season as the Rockies roared to the Wild Card, but he was beaten out for a reserve outfielder role this spring by Scott Podsednik. But if being passed over affected Smith, it wasn’t evident in his performance: .321/.442/.509 in 159 at-bats, mostly in left field, for the Sky Sox.

A second-round pick from Mississippi in 2004, Smith twice has hit 45 or more doubles in a season, once for high Class A Modesto in 2005 and again for Double-A Tulsa in 2006, when his 46 led all minor leaguers.