They open a four-game series in Philadelphia on Monday night seeking a fourth straight win over the Phillies.
The Pirates (74-68) recovered from a four-game losing streak with a three-game sweep of the Chicago Cubs. Sunday's 10-4 win vaulted them past Milwaukee and Atlanta, and they did it with a season-high 19 hits and four home runs.
Andrew McCutchen and Neil Walker both went 3 for 5 with a homer to put the team in a position to match a season-best four-game winning streak.
"Offensively, we showed up early," manager Clint Hurdle said. "We got some pitches out over the plate and we elevated some and got good swings on them. We played defense, we pitched and we hit a little bit. It was a good weekend for us."
Walker's 19th blast of the year matched Bill Mazeroski's 1958 club record for a second baseman, but he's never homered in 11 games at Citizens Bank Park.
They'll need more strong offense if Jeff Locke's form is anything like it was last week.
Locke's latest start was likely his worst of the season as he allowed five runs and four hits while walking five in three-plus innings of Tuesday's 6-4 loss in St. Louis.
Locke (6-4, 3.75 ERA) had been 3-0 in his previous four starts, but his control issues finally caught up with him. The left-hander has walked 19 batters in five starts.
"I didn't have any command. I fell behind everybody," Locke told MLB's official website. "I got them in counts where either they got their pitch to hit, or could just take. They were really in the driver's seat the whole time."
A matchup with the Phillies could do him some good. Locke has won all three of his starts against them with a 1.37 ERA and .176 opponents' batting average. He's held Jimmy Rollins hitless in nine at-bats, NL batting title contender Ben Revere is 1 for 8 and Domonic Brown is 1 for 7. Marlon Byrd is 2 for 4 with a home run.
The Phillies (66-76) narrowly missed out on a three-game sweep of Washington after losing 3-2 Sunday, but they've won nine of 13 and four straight at home.
Pittsburgh, though, has won nine of the last 12 meetings and five of six in Philadelphia. It will try to extend that run against Kyle Kendrick (8-11, 4.77), who had his best start of the season in Tuesday's 4-0 win in Atlanta. The right-hander limited the Braves to three hits in seven innings to win his third straight start.
"The season's not over, definitely," Kendrick said. "I've got four starts to finish strong. Shoot, finish on a good note and put myself in a good position. You want to finish healthy, that's the main thing. But try to take one start at a time and put up quality starts."
Alvarez is expected to travel with the team to Philadelphia, but the Pirates are considering sending him back to Pittsburgh for further tests on his injured foot that has kept him out of the lineup since Aug. 26. He pinch hit on Friday but hasn't played since.
Fellow infielder Josh Harrison was out of the lineup for a second straight game after aggravating a left ankle injury.