TUCSON, Ariz. -- Todd Wellemeyer started in 80 of his first 81 Minor League outings, then made 119 relief appearances in parts of five Major League seasons before receiving a start.

His ERA soared from a career-best 3.71 in 2008 to 5.89 last year.

Wellemeyer thus delivered an honest appraisal when he said, "My career's never been easy to read. It's always been jumbled."

He might be on the brink of simplifying matters for himself.

Wellemeyer strengthened his candidacy Friday for the fifth starter's job by becoming the first Giant to work four innings this spring. He blanked the Colorado Rockies on two hits while throwing only 41 pitches, including 27 strikes, to pace the Giants to a 9-2 Cactus League victory.

"He looked like it was midseason," Giants manager Bruce Bochy said.

Wellemeyer's most serious competitor for the No. 5 spot is Madison Bumgarner, the organization's top pitching prospect, who has walked four and struck out none while compiling a 4.50 ERA in two exhibition appearances. With off-days scheduled for the first four Thursdays of the regular season and in seven of the season's first eight weeks, the Giants may not need a fifth starter until April 14 and might not regularly use one until mid-May.

So they could decide that giving the 20-year-old Bumgarner steady work in Triple-A Fresno's rotation might make more sense. With his veteran's savvy and ability to start or relieve, Wellemeyer, 31, might be a better choice to open the season with the Giants.

"He wants to start, I'm sure, but he knows the situation," Bochy said of Wellemeyer. "He's a pro. You can tell that he knows what he's doing out there."

Wellemeyer refuses to obsess over the possibilities.

"I was one of those guys when I was young to think too much out there and try to do too much," said Wellemeyer, who has allowed two runs in nine innings spanning three exhibition appearances. "All it comes down to is executing your pitches."

That became a chore for Wellemeyer last year, when he finished 7-10 with St. Louis after posting a 13-9 mark in 2008. His ERA wasn't his only inflated statistic from 2009. Opponents hit .328 and recorded a .907 OPS (on-base percentage plus slugging percentage) against Wellemeyer, the highest figures among National League pitchers amassing at least 120 innings.

Wellemeyer's understandable insistence on clinging to his effectivness of 2008, his first Major League season as a full-time starter, may have unwittingly doomed him last year. Not only did he pitch a careeer-high 191 2/3 innings in '08, which may have drained him physically, but he also continued to throw twice a week during the entire offseason.

"I never gave my arm a rest," he said. "I didn't want to lose the feeling of that release point."

Despite his slump, Wellemeyer was highly sought in free agency -- to an extent. He drew interest from a sizable group of clubs, including the Brewers, Astros, D-backs, Dodgers, Orioles, Mets, Rockies and Phillies. But none offered him a guaranteed Major League contract. He finally signed a Minor League deal with the Giants on Feb. 10, just eight days before San Francisco's first workout for pitchers and catchers. He'll earn $1 million with a possible $500,000 in performance bonuses if he makes the Opening Day roster.

"I wanted to go to a team that wanted me. These guys seemed like they did," said Wellemeyer, who's 29-29 with a 4.74 ERA in 195 big league appearances (64 starts) with the Cubs, Royals and Cardinals since 2003. "It seemed like a good opportunity with a young group of guys in a good city and a good market."

Wellemeyer's unfazed by the challenge of proving himself all over again, though he observed, "You spend your whole career to get to be a free agent and then you've got to make the team."

Asked if that seemed ironic, Wellemeyer replied, "It is. But I'm not looking for a handout. I feel good right now. I feel like I did two years ago."