(Photo credit: Matt Marton-USA TODAY Sports)

Joshua Palacios' three-run homer highlighted a seven-run fourth inning, and Connor Joe added a two-run shot, as the visiting Pittsburgh Pirates earned a rare victory over Chicago, beating the Cubs 13-7 on Wednesday night.

Joe, rookie Jared Triolo, who also homered, and Ke'Bryan Hayes had three hits apiece for the Pirates (71-81), who built a big lead, then sweated some to beat Chicago (79-73) for just the second time in 12 meetings this season. The Cubs won Tuesday's opener 14-1.

Pittsburgh, which recorded 15 hits, trailed 1-0 after three innings, but opened the fourth with six straight singles that ended the night for Cubs ace Justin Steele (16-5). Chicago native Jack Suwinski had an RBI hit and Henry Davis delivered a two-run single to right during that opening surge. Palacios' drive into the center-field shrubbery, with two men on, off Jose Cuas capped the breakout frame.

Pittsburgh went ahead 8-1 on Triolo's solo homer in the fifth. However, Chicago roared back with five runs in the bottom of the frame against the Pirates' own All-Star, Mitch Keller (13-9), who was charged with seven runs and nine hits over 5 2/3 innings.

Christopher Morel opened the inning with a towering homer to left field. Keller then loaded the bases with one out, and Pittsburgh native Ian Happ went deep into the right-center-field bleachers to make it 8-6.

Pittsburgh, though, answered in the sixth against Mark Leiter Jr. The Pirates put runners on first and third with nobody out, and went up 9-6 on Bryan Reynolds' RBI fielder's choice. Joe clubbed his 11th homer, with a man on, to widen the visitors' cushion.

Fighting for a National League postseason spot, the Cubs have dropped nine of 12, and three straight starts by Steele, who was charged with six earned runs for a second consecutive outing while exiting before getting an out in the fourth.

Chicago opened the scoring in the second as Cody Bellinger doubled and scored on Seiya Suzuki's lined single to left. Miles Mastrobuoni had three hits for the Cubs.