The San Francisco Giants hope to pad their lead atop the National League West standings on Monday when they begin a three-game series with the Colorado Rockies at Coors Field.

The Giants now hold a 5 1/2-game advantage in the division after taking two of three from the Los Angeles Dodgers over the weekend. In Sunday's finale, Hunter Pence knocked in two runs and Barry Zito tossed 6 1/3 scoreless innings, propelling San Francisco to a 4-0 win.

"I thought this was a critical game for us to win," Giants manager Bruce Bochy said. "A lot of good things happened out there. We played very well."

Zito (11-8) gave up four hits while striking out four and walking three for San Francisco, which went 3-3 on a six-game homestand.

The Giants have now won 13 of their last 18 games within the division.

Getting the call in Monday's opener will be righty Ryan Vogelsong, who is 12-7 with a 3.29 ERA. Vogelsong did not get a decision on Tuesday against Arizona, but did not pitch well, as he surrendered six runs and nine hits in 3 1/3 innings of an 8-6 loss.

"I thought he had good stuff," Bochy said. "The pitches might have caught up with him. He was working hard out there and his pitch count got up, and that might have taken a toll."

Vogelsong beat the Rockies the last time he faced them and is a perfect 5-0 lifetime against them with a 2.22 ERA in 11 games (6 starts).

Colorado will counter with righty Alex White, who has lost his last five decisions and is winless in his previous 12 starts. White pitched well in a loss to Atlanta on Wednesday, as he gave up just two hits and an unearned run in four innings. He did walk four batters, though, in the 1-0 loss.

"I had good stuff," White said afterward. "I made some good pitches, got some guys out and kept us in the game."

White is 0-2 in three starts against the Giants with a 7.90 ERA.

Colorado enters Monday's series riding a five-game losing streak after getting swept in a doubleheader by the Philadelphia Phillies on Sunday. The Rockies actually led the nightcap, 4-1, but committed five errors on their way to a 7-4 loss and have now dropped six of seven.

"We can't make five errors and win, it's that simple," Rockies manager Jim Tracy said.

San Francisco is 8-3 against the Rockies this season.