Humberto Cota drove in four runs to support only the second effective start by Perez all season and the Pirates roughed up Jennings for all of their runs in an 8-3 victory Saturday night.
Cota had a three-run double in a five-run second inning against Jennings (1-6), a former first-round draft pick whose mostly miserable season got even worse. Jennings has allowed 29 earned runs in his last five starts and has won only once in 17 starts, dating to last Aug. 22.
The big inning followed the usually low-scoring Pirates' six-run seventh inning in their 9-4 win Friday. The Pirates came into Saturday's game with 150 runs, the fewest in the majors, and had scored only 14 runs in five games heading into this series.
Perez's season hasn't been much better than Jennings', until now, as he gave up at least five earned runs in six of his first eight starts. But a two-week layoff to refine his mechanics and ease the discomfort in his sore left shoulder seemed to have made a big difference in Perez, one of the majors' top young starters last season with a 2.98 ERA and 239 strikeouts.
"I was just as anxious as anyone to see what we would get," manager Lloyd McClendon said. "Obviously, he was a little rusty but, overall, we're pleased. What I liked was his slider was biting the way it did last year ... and he finished guys off."
Perez (2-4) fought streaks of wildness -- he needed 57 pitches in the first three innings, despite not allowing a hit -- but also looked dominating at times with eight strikeouts in five innings.
Fittingly enough, the Pirates had previously scheduled a Perez bobblehead doll giveaway, and the left-hander was glad the sellout crowd of 37,504 went away with more than just a prize to remember him by.
"It was a special day," he said. "I liked this day."
So did the Pirates -- especially Cota, who said Perez "was the last missing piece we needed" on what otherwise has been a mostly effective starting pitching staff. Pirates starters are 8-1 with a 2.32 ERA in their last 11 starts, during a stretch that has seen Pittsburgh win 11 of 16.
Cota, like Perez, is from Mexico and often is the left-hander's biggest supporter and, when necessary, his sharpest critic. Cota gave Perez plenty of support this time with his bases-loaded double, a run-scoring single and a career-high four RBI.
"I was glad I could do my job ... so we could give him a lead and get him going," Cota said.
Perez was lifted with an 8-2 lead after giving up two hits and two runs, both on Matt Holliday's two-run homer in the fourth. Colorado's only other hit off Perez in its 17th loss in 19 road games was Luis Gonzalez's single in the fifth.
Perez's only better start was a 2-0 victory over Houston on April 25 that saw him pitch 7 2/3 shutout innings. But he followed that with two awful starts, giving up 14 runs in 10 1/3 innings in losses to the Giants and Diamondbacks, and the Pirates decided to shut him down.
"I tried to think like this was my first start and to just forget about all that happened," Perez said.
"He made bad pitch after bad pitch," said bench coach Jamie Quirk, who filled in as manager because Clint Hurdle was in Denver with his hospitalized 2-year-old daughter. "He's in a funk. ... There are certain points in a player's career where you've got to say, `I'm going to get it done.' And I think he's at that point. He's just got to say, `I'm going to get better, There's no more getting worse."'
Jennings was clearly frustrated with his latest failed start.
"I'm trying to get things rectified and I know I will, it's just a struggle right now," he said. "I'm not giving us much of a chance."
- Nine of Cota's 13 hits are for extra bases.
- Mike Gonzalez pitched the final 1 1/3 innings for his first save because the potential tying run was on-deck when he entered in the eighth.
- Jennings has lost four in a row, allowing at least four runs in each.
- The Pirates played their 10th consecutive errorless game.
- McClendon became the 10th Pirates manager with 300 career victories.
- Pittsburgh is 12-5 against Colorado the last three seasons.
- The Rockies haven't won any of their six series in PNC Park.