Cincinnati ? Wily Mo Pena sure relished the biggest hit of his career.

Pena came through with a pinch-hit grand slam in the seventh inning, capping a six-run rally that sent the Cincinnati Reds past the slumping Pittsburgh Pirates, 6-4, Friday night.

“I hit a grand slam earlier this year, but this is the biggest because we won the game, and my team’s happy,” Pena said.

Before the game, the Reds honored Ken Griffey Jr. for hitting his 500th home run Sunday in St. Louis. The ceremony included a video montage of some of his most noteworthy home runs and other career highlights.

Griffey went 0-for-3 with a walk to fall to 1-for-19 since his historic home run. He’s hitless in his last 16 at-bats.

But Pena gave the Reds their sixth consecutive two-out hit in the seventh as Cincinnati wiped out a 4-0 Pittsburgh lead and sent the Pirates to their 16th loss in 19 games.

“Strange things are happening around here,” said Pittsburgh starter Kip Wells, who took a no-hit bid into the sixth inning but wound up with a no-decision.

It was Pena’s second slam of the season and seventh homer overall. It also was the first pinch-hit grand slam by a Reds batter since Russell Branyan connected off Milwaukee’s Brooks Kieschnick last July 21.

Jason LaRue started the rally with a double down the left-field line and moved to third on Juan Castro’s single to right. Pittsburgh manager Lloyd McClendon replaced Wells with Brian Meadows, and Tim Hummel and pinch-hitter Jermaine Clark each hit a run-scoring single.

Salomon Torres (4-3) walked Ryan Freel and was replaced by left-hander Mike Gonzalez. Reds manager Dave Miley sent Pena to bat for switch-hitting D’Angelo Jimenez, whose pulled left side muscle makes swinging from the right side uncomfortable.