DENVER -- The evolution of a ballplayer doesn't always have to be marked by such grandiose gauges as home runs and RBIs.

Sometimes, the progress can be a little more subtle.

In Ian Stewart's case, that sign of maturity came in the form of an 11-pitch walk that began a two-run rally in the second inning of Saturday's game.

Reds pitcher Edinson Volquez unleashed his entire arsenal -- fastball, changeup and slider -- but Stewart remained patient and fouled off several nasty pitches to keep the at-bat alive. When Volquez finally made a mistake, Stewart was disciplined enough to lay off and draw the walk.

"[Volquez] threw the whole kitchen sink at him, and he stayed in there and battled," Rockies manager Clint Hurdle said. "I think that's one of his other big steps he's been able to take."

Earlier this season, an overanxious Stewart would have likely ended the at-bat with a strikeout. During his first stint with Colorado, Stewart struck out more than 50 percent of the time (28 out of 55 at-bats) and drew just three walks in 18 games.

Since his recall from Triple-A Colorado Springs on July 19, Stewart has improved in all facets of the game, which can be directly attributed to his increased patience at the plate.

In 33 games, he's walked 19 times and kept his strikeouts to a manageable 32. Stewart was named the Rookie of the Month in July, and his .440 average with runners in scoring position leads the Majors.

"His discipline has improved," Hurdle said. "He's taking some pitches early to get himself in hitter's counts. When balls are in the zone, he's firing. He's very aggressively selective, and obviously the [pitch] recognition has improved to handle the offspeed stuff as well.

"Just a lot of nice improvements offensively, across the board."