Reyes worked six economical innings to end a slump that began last September, helping St. Louis beat the Milwaukee Brewers 5-2 on Saturday night to sweep a day-night doubleheader.
The assignment was envisioned as a cameo, but the Cardinals are starved for starters and manager Tony La Russa and pitching coach Dave Duncan were reconsidering sending Reyes back to Triple-A Memphis.
Reyes, who entered the game with a 6.40 ERA, retired 15 of the last 16 hitters he faced.
"You get what you earn, and he definitely earned a big game for us," La Russa said. "It's nothing official, but I told Dunc and a couple of coaches, 'You've got to evaluate whether you give Anthony another start.'"
The Brewers have lost four of five, and their NL Central lead was shaved to 1½ games over the Cubs with the Cardinals seven back in third place. It's the closest the defending World Series champions have been to the lead since June 14 when they were 6½ games back.
"This season has been up and down," Albert Pujols said. "Hopefully we play the best baseball ever the last two months."
Milwaukee is 21-31 on the road, losing 10 of their last 13, to go with an NL-best 36-17 at home. The Brewers' lead hasn't been this slim since April 22 when they also led by 1½ games.
"It's important for me and our team in general to keep expecting good things to happen," Game 2 loser Chris Capuano said. "When you have a day like today, it's a long, tough day and there's a lot of negativity around."
Reyes (1-10) was recalled earlier in the day. He avoided first-inning trouble that has dogged him all year and needed only 67 pitches to get through six innings, allowing two runs on two hits.
"It's a weight off my shoulders," he said. "It was probably the hardest one I've ever had to get, so it was pretty nice."
Jim Edmonds had a two-run single and Scott Rolen had an RBI double in a three-run first off Capuano (5-7) that could have been much bigger without Pujols' double-play ball. Capuano allowed four runs in 6 1/3 innings and is 0-7 with a 6.16 ERA in 12 starts since May 7, after going 5-0 with a 2.31 ERA in his first seven outings.
"Cappy was kind of in the same boat his last 11 starts," manager Ned Yost said. "Something had to give. I was just hoping it was our guy that it gave for."
Reyes, who dominated the Tigers while pitching into the ninth in Game 1 of the World Series, won his first regular-season game since Sept. 3, 2006, against the Pirates. His start this year tied a franchise record for futility with Kid Carsey, who began the 1898 season 0-10.
Geoff Jenkins had a sacrifice fly in the second and Corey Hart hit his 16th homer in the sixth for the Brewers, who trailed 3-2 before RBI singles by Pujols and Juan Encarnacion in the seventh off Matt Wise put the Cardinals ahead 5-2.
- Before Game 1, the Cardinals recalled Brian Falkenborg from Triple-A Memphis and optioned RHP Kelvin Jimenez to Memphis.
- The Cardinals are 24-25 at home after going 49-31 in the first year at new Busch Stadium.
- Game 2 drew paid attendance of 45,829, largest of the season, with about 2,000 no-shows. Game 1 attendance was 45,089, marred by 12,283 no-shows.