PITTSBURGH — The Los Angeles Dodgers were trying to clinch a division title. Andy LaRoche was having none of it.

LaRoche, 26, considered one of the top prospects in the Dodgers' organization only last year, put together a career day against his former club Monday at PNC Park.

With the Pirates playing their final home game of the season, the third baseman went 5-for-5 with two home runs, two doubles, a single, six RBI and four runs scored in the Bucs' 11-1 victory.

"Believe me, it feels good to be able to have a day like that against anybody," LaRoche said. "The fact it was the Dodgers has no special significance to me."

The Dodgers' magic number for clinching the National League West remains at one. They will now try for the clincher tonight in San Diego.

The Pirates are simply trying to avoid a 100-loss season. They must go 4-3 on their final road trip of the season to fall short of that mark.

LaRoche had never hit two home runs in a game, collected as many as four RBI or four hits in a game before Monday. Only one other Pirate put together a five-hit game this season: Freddy Sanchez on May 25 at Chicago's Wrigley Field.

LaRoche hit over .300 with moderate power in three straight minor league seasons in the Dodgers' system, but he collected just 33 hits and three home runs in 152 at-bats in parts of two seasons in the majors before being dealt to the Pirates at the 2008 trade deadline.

"There are no ill feelings between me and the Dodgers," LaRoche said. "I had heard the trade rumors and they had a chance to get Manny Ramirez.

"A chance to get one of the best hitters in the history of the game? I would have traded me, too. Besides, I got a chance to play with my brother (first baseman Adam) and play regularly in the major leagues. It worked out well for me."

Upon coming to Pittsburgh, LaRoche hit only .152 — 25 for 164 — in 49 games last year.

"Nobody thought he could play at this level last year," Pirates manager John Russell said. "I think he's made major strides this year. He's had his ups and downs at the plate, but he appears to have figured it out. And he's been outstanding defensively."

LaRoche has 12 homers and leads the Pirates with 61 RBI. His batting average is at .259, but it's been all over the place: .254 in April, .330 in May, .245 in June, .162 in July, .205 in August and .333 so far this month.

In his last 14 starts, LaRoche is hitting .372 with five homers and 13 RBI. He ranks fourth among NL third basemen with 136 starts, most by a Pirates third baseman since Aramis Ramirez had 155 starts in 2001.

"Andy is definitely one of those guys we're figuring will be an improved player coming out of spring training next year," Russell said. "We've got a few of those."

All of LaRoche's hits Monday were solid, with the possible exception of his home run to center field in the fourth inning.

"That one might have been wind-aided," he admitted. "I hit that ball pretty high."

He singled to right on an 0-2 pitch in the first inning and doubled to center in the second. With a chance to hit for the cycle in the sixth, his liner to right-center rolled to the wall.

"I was thinking triple, but (third-base coach) Tony Beasley held me up," LaRoche said. "I thought about running through the stop sign, but I wound up scoring, so it was all good."

LaRoche added to his career day by homering off the left-field foul pole in the eighth.

"This was a fun way to close out the home schedule," he said. "I feel like I've found my stroke again. I have to keep it this time."

Starting pitcher Zach Duke (11-15) was in control from the start, allowing only three singles before giving up a triple with one out in the ninth — a low total for a pitcher who has allowed an NL-high 225 hits.

Duke couldn't believe it when Russell lifted him following Chin-Lung Hu's sacrifice fly, with a 10-run lead and only one batter to retire for the complete game, and the fans let Russell have it. Even Dodgers third base coach Larry Bowa seemed surprised, saying something to Duke as he walked by.

"I wanted it pretty bad, I'm not going to lie," said Duke, who is arbitration-eligible and thus lost a complete game he could have used in negotiations.

The Associated Press contributed to this report.