Since then, he's had to work hard to keep it.
With the Rockies having faced three left-handed pitchers against the Phillies, Garrett Atkins took all of the starts. But when the Rockies return home for an important four-game set with the Cubs, Stewart's turn will come again.
Before taking his spot in the dugout for Thursday afternoon's game with the Phillies, Stewart sweated through an intense batting-cage session.
"I felt good in Cincinnati," Stewart said. "I was seeing the ball well. I hit some balls hard. I was in a good spot there."
Stewart hasn't had a problem hitting balls hard. He is second on the club with 18 home runs -- several of the majestic variety -- and third with 52 RBIs. However, he is hitting .227 in 100 games, mostly as the team's primary third baseman. Atkins, who has slumped all season, actually started Thursday at .231.
Rockies manager Jim Tracy said once Stewart is not far from becoming a more complete hitter. Tracy said he has seen several cases when the pitcher leaves a pitch in a good location and Stewart has missed it or fouled it. Often, Tracy noted, pitchers rarely give those chances in the Majors.
"You've got to be ready to fire, and you have to square it up and get it in play," Tracy said.
Stewart said the key for him is not to overswing when that pitch comes. An example of a good swing came Saturday night, when he singled off the Reds' Homer Bailey to drive in two runs with the bases loaded. The next day, Bronson Arroyo left a changeup over the plate. With a relaxed swing, Stewart homered.
"I try not to get too big when I see that one good pitch to hit," Stewart said. "It's not always easy."
Stewart said early in the year when he was striking out at a high rate, he became tentative and compounded his problems. Now he'd like to raise his batting average, but he's beyond letting his low number affect his aggressiveness in the batter's box.
"I'm just concentrating on driving the ball, not avoiding strikeouts," Stewart said. "That makes me a better hitter.
"I think about average, just because of my own personal goals. I'd like it to be a little higher. But I feel I'm helping the team now."
Thomas Harding is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.