SAN FRANCISCO(AP) Tim Lincecum doesn't keep track of such things as scoreless innings streaks. He does know he's on a roll that might just earn him the starting nod for National League in the All-Star game.

''It would mean a lot - the hard work paid off,'' said Lincecum, who missed last year's Midsummer Classic because of an illness and was hospitalized. ''If I do happen to start, it will make up for the fact I didn't even make it to the field last year.''

NL manager Charlie Manuel of the World Series champion Phillies will certainly notice Lincecum's recent run.

Lincecum (9-2) extended his career-best scoreless innings stretch to 23 in winning his third straight start and also scored the first run in the San Francisco Giants ' 9-0 victory over the Houston Astros on Saturday.

''Obviously Timmy has the numbers to go out there and start,'' center fielder Aaron Rowand said of the All-Star game. ''Timmy's got to be in the running.''

The reigning NL Cy Young Award winner struck out nine and allowed three hits with two walks in seven innings. Brandon Medders and Merkin Valdez each pitched an inning to finish the three-hit shutout, the Giants' majors-best 11th and fourth in their last seven games.

San Francisco had 12 hits a day after producing a season high in runs and pounding 15 hits in a 13-0 victory Friday night.

Pablo Sandoval singled home Lincecum in the fifth and Randy Winn added a two-run double and scored on a passed ball in the inning that got by Astros catcher Ivan Rodriguez . Aaron Rowand added a two-run single and Bengie Molina an RBI double.

''It was a good game there for a while and then it got away from us,'' said Houston's Lance Berkman , whose double was the team's only extra-base hit.

Lincecum, expected to be named an All-Star on Sunday for the second straight year, outpitched former Giant Russ Ortiz (3-4). Lincecum struck out Michael Bourn looking on his third pitch of the game. After Lance Berkman doubled to start the fourth, Lincecum struck out the side.

He has gone 18 consecutive innings without allowing a baserunner past second.

''He's throwing as well as I've seen him since he's been here and that's saying a lot,'' manager Bruce Bochy said.

Lincecum - coming off back-to-back complete games - walked in the fourth and later scored, then drew another free pass in the fifth to load the bases before Rowand's single. Winn doubled and Sandoval was intentionally walked before Ortiz's day was done. He received a warm ovation as he walked off the mound.

Lincecum's scoreless streak is the longest by a Giant since Robb Nen went 25 2-3 consecutive innings without allowing a run in 2000. Lincecum has won six of his last seven decisions.

''It's kind of one of those rolls you don't notice until it keeps going and going and going,'' he said. ''You keep feeding off the goose eggs, I guess.''

The Astros were shut out in consecutive games for the second time this year, also April 12-13 at St. Louis and Pittsburgh. The Giants shut out Houston in back-to-back games for the first time since Sept. 22-23, 1993.

''He's got a good arm,'' Astros manager Cecil Cooper said of Lincecum. ''What else can you say? Good pitching can make you look bad, flat.''

Ortiz struck out a season-high seven but lost his second straight decision and saw his winless stretch reach six starts.

He was a former fan favorite during six seasons covering two stints with San Francisco, last in 2007. He was the Giants' Game 6 starter in the 2002 World Series when the club collapsed and lost in seven games to the wild-card Angels.

The right-hander was a fourth-round draft pick by the Giants in 1995 and went 69-47 during his time with San Francisco. This marked his eighth appearance against his former team - and he is 0-4.

Sandoval bruised his right knee sliding wildly into home in the fifth but it wasn't considered serious. He was out on the play.

NOTES: Lincecum went 16 scoreless innings last season. ... He is 2-0 in five career starts vs. Houston and has never allowed a home run to the Astros. ... The Astros are 14-10 in day games. ... Houston is 15-7 against the NL West. ... A home-plate ceremony was held before the game on the 70th anniversary of Lou Gehrig 's luckiest man speech.