San Francisco @ Colorado preview

Last Meeting ( May 20, 2014 ) San Francisco 4, Colorado 5

The San Francisco Giants hope to have both Buster Posey and Angel Pagan back in the lineup Wednesday, when they visit the Colorado Rockies for the middle contest of their three-game series. Posey missed Tuesday’s game due to nerve irritation in his back but indicated he was available as a pinch hitter and doesn’t believe the ailment will force him to the disabled list. Pagan, who is off to an impressive start with a .321 average and 15 RBIs, expects to play Wednesday after missing one game with a sprained left shoulder.

The Rockies are coming off one of their most dramatic wins of the young season as they rallied for a 5-4 win on Tuesday, when Nolan Arenado hit a two-run double off Sergio Romo with two outs in the ninth inning. Wilin Rosario, who blasted a two-run homer and had three RBIs in the win, is showing signs of returning to full strength after missing 12 games with a viral infection. Colorado's young catcher has raised his average to .250 with four hits in his last 11 at-bats.

TV: 8:40 p.m. ET, CSN Bay Area (San Francisco), ROOT (Colorado)

PITCHING MATCHUP: Giants RH Matt Cain (1-3, 4.33 ERA) vs. Rockies RH Jhoulys Chacin (0-2, 4.76)

Cain snapped a winless streak of 11 starts on Thursday by holding Miami to four runs on six hits over 7 2/3 innings. The 29-year-old has allowed 13 runs over his last three outings covering 18 2/3 frames and has walked at least three batters in four of his last five starts. Troy Tulowitzki is batting .333 (21-for-63) with five homers against Cain, who went 0-1 with a 5.54 ERA in two starts against the Rockies last month.

Chacin has been unspectacular in three starts since coming off the disabled list, but manager Walt Weiss was encouraged by his six-inning outing against the Royals last Wednesday. “I’d like to see him keep taking strides forward,” Weiss told the Denver Post. “He’s starting to settle in. We’re going to need him to be a guy at the top of the rotation, like he was a year ago.” Pablo Sandoval is 8-for-27 with two homers against the 26-year-old Chacin.

WALK-OFFS

1. The Giants are 20-4 when scoring first.

2. Colorado OF Michael Cuddyer returned from the 15-day disabled list on Tuesday and went 0-for-4.

3. San Francisco OF Hunter Pence is the majors’ active leader in consecutive games played at 352.

PREDICTION: Giants 7, Rockies 4