Not that the St. Louis backup is complaining.
Carpenter scored the winning run with a picture-perfect slide on Allen Craig's single in the 10th inning, giving the Cardinals a 5-4 win over the Milwaukee Brewers.
The Cardinals broke a three-game losing streak and avoided a three-game sweep. St. Louis held onto its slim lead for the second NL wild-card spot.
Carpenter singled with one out in the 10th off Kameron Loe (6-5) and moved up on a wild pitch. Craig singled to right field with two outs and Carpenter barely eluded the tag from catcher Jonathan Lucroy after a strong throw by Aoki.
''I had an angle and I just tried to avoid the tag and thankfully I got in there,'' Carpenter said. ''I got some new blood from that.''
Carpenter sustained five cuts on his hands Saturday when his bat shattered in a 6-3 loss. He left the game in the third inning as blood dripped from his hands.
Carpenter showed up early Sunday and went through some hitting and throwing drills to prove to manager Mike Matheny that he was fit to play.
''The work ethic he has, the energy he brings, he's a very good teammate,'' Matheny said.
Carpenter used a super glue to tape his skin back in place on one of the cuts. He simply taped the others shut.
Now, thanks to his game-winning slide, he has two other cuts and one huge scrape on his bruised hands.
''It's sore, but it's nothing that would keep me out,'' he said. ''Once you get that adrenaline going, you don't think about it.''
Craig recorded his first career walk-off hit, thanks in part to Carpenter's hustle.
''It's a great feeling,'' Craig said. ''The last few days haven't been so great. It was good to battle back after a tough game.''
The loss slowed the Brewers, who were trying to reach the .500 mark for the first time since April 24.
Milwaukee manager Ron Roenicke was pleased with his team's performance and its ability to bounce back in the ninth.
''We played a really good game today, they just came through with a really big hit,'' he said. ''I'm OK with the three games we just played.''
Lance Lynn (14-7) picked up the win with one inning of scoreless relief.
Beltran ended an 0-for-14 slump. He had not gotten an extra-base hit in his previous 49 at-bats.
''It was good for me to go out there and get a couple hits,'' Beltran said. ''Lately, it's been a battle at the plate.''
St. Louis pushed the lead to 4-1 in the second on doubles by pitcher Joe Kelly and Carpenter.
Milwaukee climbed to 4-2 in the fourth on singles by Corey Hart, Jonathan Lucroy and Jean Segura.
Segura, who had a career-high three hits, doubled with one out in the ninth off Motte. One out later, Aoki hit his eighth home run.
NOTES: Brewers OF Ryan Braun left in the sixth with a sore wrist. 1B Corey Hart, who has a hit in his last 11 games against St. Louis, left the game after twisting his ankle on the last play of the fourth inning. ''He tweaked it a little bit and he's got a mild sprain,'' Roenicke said. Braun and Hart were listed as day-to-day. ... Cardinals 3B David Freese missed the game with a mild left ankle sprain. He is considered day-to-day. ... St. Louis reliever Edward Mujica pitched a scoreless seventh inning. He has not allowed a run in 18 appearances since coming to the Cardinals in a July 31 trade. ... The Cardinals improved 4-10 in extra innings. ... St. Louis opens a seven-game road trip at San Diego on Monday. Jaime Garcia (4-6, 4.16) will face Eric Stults (5-2, 2.35). ... Milwaukee begins a six-game homestand against Atlanta. Wily Peralta (1-0, 5.14) takes on Mike Minor (8-10, 4.58).
Link to boxscore: St. Louis 5, Milwaukee 4 (10 innings)