SAN FRANCISCO -- When starting pitcher Matt Cain takes the mound Tuesday night against the Chicago Cubs, the Giants will be three strikeouts away from making history.

If Cain strikes out three Cubs batters, the Giants will have three starting pitchers with 100 or more K's before the All-Star break for the first time in the San Francisco era. Tim Lincecum, who could be headed to his first All-Star Game, leads the team with 114 followed by Jonathan Sanchez (102) and then Cain, who has 97.

Sanchez, who was named the National League Player of the Week on Monday, said he and Lincecum made a friendly bet as to who would have more strikeouts at the end of the season. Sanchez said it was more of a joke, but now it appears a dark horse has entered the race with Cain on the verge of getting his 100th strikeout.

"We're all having fun," Sanchez said. "[Lincecum] strikes out a lot of people, but I'm close. I have to strike out 12 more, but he's going to start again before me."

Cain said he heard about the competition but it's something the three don't talk about.

"Timmy and Sanchez have both punched a lot of tickets this year. We know what they can do," Cain said. "It's definitely not something we sit around and talk about; it's more of an unspoken competition."

Cain, who is 3-2 with a 4.09 ERA in five starts against the Cubs, will take the mound looking to win his fifth game of the season. In five starts against the Cubs, Cain has struck out 24 batters.

"We all push each other to do better," Cain said. "When Lincecum and Sanchez have good outings, I get motivated to go out there and do just as good. We all seem to be pitching well right now."

Pitching matchup
SF: RHP Matt Cain (4-6, 4.44 ERA)
Cain struggled in his last outing, allowing four runs and eight hits in five innings at Cleveland. That interrupted a three-game stretch in which he was 2-1 with a 2.95 ERA, 25 strikeouts and only three walks in 21 1/3 innings. Cain's appearances against the Cubs conjure an indelible memory: On Sept. 9, 2005, he became the youngest Giant in the franchise's San Francisco history to throw a complete game when he beat Chicago with a two-hitter. Cain finished 1-1 with a 5.73 ERA in two starts against the Cubs last year.

CHC: RHP Jason Marquis (6-4, 4.96 ERA)
The Orioles made sure Marquis wouldn't go 5-0 for June his last time out, shelling him for seven runs in four innings. He had been stellar previously, outdueling Brad Penny, Roy Halladay and Jose Contreras in consecutive outings. The start was Marquis' shortest of the season and his first loss since May 13. Marquis is 3-0 with a 2.56 lifetime ERA against the Giants.

Tidbits
Second baseman Ray Durham was out of the lineup Monday and is day-to-day after suffering a knee bruise in Sunday afternoon's game against the A's. ... Outfielder Dave Roberts, who has been out of the lineup since April 7 because of surgery on his left knee, is continuing to progress. Roberts ran the bases prior to Monday night's game and said his knee felt good. Roberts is expected to start a rehab assignment as soon as Friday. ... Outfielder Daniel Ortmeier, who is recovering from a broken left middle finger, is expected to start taking batting practice this week. Ortmeier said his finger is healed but he has not yet been given a timeline for his return. ... Double-A catcher Pablo Sandoval has been added to the World team for the XM Satellite Radio All-Star Futures Game on July 13 at Yankee Stadium.

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On the Internet
 MLB.TV
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Up next
• Wednesday: Giants (Kevin Correia, 1-5, 4.79) vs. Cubs (Ryan Dempster, 9-3, 3.26), 7:15 p.m. PT
• Thursday: Giants (Tim Lincecum, 9-1, 2.38) vs. Cubs (Sean Gallagher, 3-3, 4.36), 4:05 p.m. PT
• Friday: Giants (Jonathan Sanchez, 8-4, 3.79) vs. Dodgers (Derek Lowe, 5-8, 3.88), 1:05 p.m. PT