Right-hander Bradley Blalock will get an attempt to crack the Colorado Rockies' rotation as Brett Wisely tries to reassert himself as a staple in the Giants' lineup when the teams continue their four-game series Saturday afternoon in San Francisco.

The clubs have split the first two contests of the series. Colorado won 4-3 on Thursday before the Giants triumphed 4-0 on Friday.

Blalock (0-1, 10.29 ERA), who made the Rockies' Opening Day roster as a reliever, was sent to the minors after just two appearances, in which he allowed two runs and five hits in three innings.

He was promoted from Triple-A last week for an emergency home start against the Cincinnati Reds. The Rockies elected to push Ryan Feltner back a day while he dealt with what was considered a minor back issue at the time.

Blalock failed his exam, allowing six runs in four innings in an 8-1 loss to the Reds, but he now finds himself with a longer leash as Feltner went on the 15-day injured list Friday, retroactive to April 29.

"We just wanted to make sure that he didn't make this start on Saturday compromised," Rockies manager Bud Black said of Feltner. "The way his back felt, it would have. The back was just not in a position where Ryan felt comfortable giving it a go, and we didn't feel comfortable."

As for Blalock, acquired last July from the Milwaukee Brewers, the best Black could say at this point is, "He's rested, ready to go."

Blalock has yet to face the Giants and has just one road win to show for his two-year career -- last August at Yankee Stadium.

He will see a Giants team that has struggled offensively of late. They have been held to four or fewer runs in seven straight games, a stretch in which they've gone just 3-4 after a 17-9 start.

The Giants have only 12 extra-base hits in those seven games. They've hit five homers, all solo shots.

With Tyler Fitzgerald on the injured list with a fractured rib, Christian Koss has become the primary second baseman. But he saw his season average fall to .207 following a 0-for-2 effort on Friday. He has no extra-base hits in 33 plate appearances this season.

Enter Wisely, who batted .286 in 43 games with the big club early last season before he slumped late in the year and wound up beginning this year in the minors.

Giants manager Bob Melvin likes the fact that Wisely bats left-handed, which complement's Koss' right-handed form.

"It doesn't mean it's going to be a strict platoon. We'll see how performance goes," Melvin said. "Koss has played pretty well when he's been in there, but Wisely will get at least one game (this weekend), and then we'll see where it goes."

Right-hander Jordan Hicks (1-3, 6.12 ERA) will start on Saturday for the Giants. He has gone winless in five starts since throwing six shutout innings of one-hit ball in his first start of the season at Houston in March.

The 28-year-old did throw the first five innings of a 3-2 home win over the Texas Rangers in his most recent start last Sunday but did not get a decision.

Three of Hicks' 16 career wins have come against the Rockies, against whom he has made 10 appearances, including two starts, and has a 3-1 record and 4.58 ERA.