Cardinals rookie Tyler O'Neill hit a three-run homer during a six-run eighth inning, Marcell Ozuna drove in three and Mikolas pitched seven solid innings after an extra day off to lift the Cardinals over the Pirates 11-5 on Tuesday night.
"The extra day is big at this point in the season," Mikolas said. "Gives you an extra day to push back a lift or take that breather and get some stuff done at your own pace and not try to crunch running and lifting and throwing and treatment and this and that in a day. It allows you to space it out and it takes a mental burden off you."
Mikolas (15-5) gave up a run, five hits and a walk while striking out seven with 107 pitches. He dropped his ERA to 2.99, and he got his first victory in five starts against the Pirates this season.
"I thought he was fantastic," Cardinals manager Mike Shildt said. "He threw strikes for effect. His secondary pitches were hitting. He did a really, really nice job. It was a quality outing. Miles has been pretty good every time he's toed the rubber."
Mikolas struck out five straight in one stretch, and the Cardinals improved to 21-8 in his starts.
Pittsburgh manager Clint Hurdle was impressed with Mikolas, who signed with St. Louis before this season following three years in Japan.
"He shows up, makes pitches and he competes," Hurdle said. "For him to get the depth he got after a couple of situations we had him in early was impressive. ... We jacked his pitch count up and he was able to put his foot down when he needed to."
Ozuna is hitting .352 this season against Pittsburgh. He has 13 RBI against the Pirates and 79 on the season.
Since coming off the disabled list for his balky right shoulder, Ozuna has been hot.
He extended his hitting streak to seven games (13 for 30, .433). It was his team-leading 20th game with multiple RBI this season.
"I feel better, God bless," Ozuna said. "I'm better in my approach and having success. I'm way better."
Joe Musgrove (6-9) went six innings. He allowed four hits, four runs and two walks while striking out eight.
"That was a missile to left to get us started," Shildt said.
Corey Dickerson countered for Pittsburgh with an RBI single in the fourth before St. Louis added two runs in the sixth after loading the bases with no outs. After Ozuna struck out, Musgrove threw a wild pitch to score Carpenter. Paul DeJong hit a sacrifice fly to center, driving in Martinez for a 4-1 lead.
Then St. Louis blew it open in the eighth. Pena singled home Kolten Wong from second base, and O'Neill then hit a 3-0 pitch 457 feet into the upper left field bleachers for his eighth home run. The shot knocked out rookie pitcher Nick Burdi, who was making his major league debut.
Cardinals: Activated P Mike Mayers (right shoulder inflammation) from the 10-day disabled list. He had been out since Aug. 26. ... C Yadier Molina missed his fifth straight game with left hamstring tightness. He is day to day. ... 3B Jedd Gyorko (left groin strain) is expected to be activated Thursday.
Pirates: RHP Jameson Taillon (12-9, 3.40) make his career-high 29th start. He had made 18 straight starts allowing three earned runs or fewer. He is 2-1 with a 3.57 ERA in seven career starts against St. Louis.
Cardinals: RHP Daniel Poncedeleon (0-1, 2.67) will make his fourth start of the season and it will be his first appearance against the Pirates. He pitched two innings of scoreless relief Saturday in Detroit.
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