MINNEAPOLIS — The latest sign of Francisco Liriano's season-long struggle was this: An otherwise well-pitched game was ruined by a pair of mistakes the light-hitting Pittsburgh Pirates sent sailing into the seats.

Ian Snell won for the first time in two months and Andrew McCutchen hit his first major league home run Wednesday night, leading the Pirates past Liriano and the Minnesota Twins 8-2.

"It's really frustrating, because every time I miss one pitch it just changes the whole game," Liriano said. "I don't know what to do anymore."

McCutchen and Andy LaRoche each hit two-run shots against Liriano (2-8), who lasted seven innings but hurt himself again with a couple costly lapses in pitch location. Adam LaRoche also homered for Pittsburgh, in a three-run eighth against reliever Sean Henn, to match his little brother. The last time siblings homered in the same game for the Pirates was 1938: Lloyd and Paul Waner.

Pittsburgh has only 40 home runs in 65 games, though seven in the last six.

"Full moon, I guess," manager John Russell said.

The Pirates moved past San Francisco out of last place in the majors in the power category.

"I couldn't stop smiling after a while, because I saw seven runs on the board against a good team," Snell said. "We just played great, and I'm very grateful and thankful that I got a win."

Like Liriano, Snell (2-7) has regressed since his first full season in 2006. He hasn't received much run support this year, but after a rough May and a so-so start to June the right-hander came through with a sharp performance: six innings, five hits, three walks and just two runs.

"He pitched OK and wasn't quite as efficient as we would've liked," Russell said. "He didn't give up many hits. It's good to get a win for him, and I think that's going to be a big boost for him.

Joe Mauer doubled and scored, but even the .425-hitting Minnesota catcher made two outs against Snell after racking up four hits the night before. Mauer has hit in 37 of 43 games he's played in this season.

After the Twins peppered starter Paul Maholm for 14 hits over five innings of Tuesday's victory, Snell was much stingier. Joe Crede's two-out, two-run double tied it at 2 and atoned for his first-inning-ending flyout with two on, but Liriano soon lost the lead and Snell stayed steady.

"Seems like Ian later in the game is really good," Russell said. "We just have to find a way to get him over the hump."