Progressing through the minor leagues, he won the 2009 Harry S. Jordan Award as the Giant who did the best in his first spring training, making San Francisco's Opening Day roster as a result.

After being the Fresno Grizzlies' best starter in 2010, he was called up in mid-June when Todd Wellemeyer was injured; he made one start before being replaced by Madison Bumgarner in the rotation.

[7] His 15 wins and 167+2⁄3 innings pitched trailed only Matt Maloney's totals for the league lead, and he also finished in the top five in starts (third) and ERA (fifth).

[1] He was the league's pitcher of the week for the period ending June 23, during which he threw seven scoreless innings in a victory over the New Hampshire Fisher Cats.

[1] In 2009, Martinez won the Harry S. Jordan Award, presented annually by the Giants to a player who exemplifies performance and dedication in his first spring training.

Martinez posted a 1.72 ERA over his final five appearances of the preseason, and Giants reliever Sergio Romo was still recovering from an elbow injury.

"[10] Martinez made his MLB debut on Opening Day (April 7), relieving Tim Lincecum after the starter allowed three runs in three innings against the Milwaukee Brewers.

In what the Associated Press called a "rocky two innings", Martinez gave up two earned runs but picked up the victory, as the Giants took and held the lead in a 10–6 triumph.

[13] Two days later, in the ninth inning against Milwaukee, a line drive off the bat of Mike Cameron struck Martinez in the forehead, lacerating him and causing a nose bleed.

[11][14][15] Reporter Jeff Chiu called the incident "one of the most frightening moments a pitcher can have on the mound", adding that Martinez "was lucky not to have been more seriously injured on the play".

[16] On August 28, he was optioned to the Class AAA Fresno Grizzlies of the Pacific Coast League after giving up eight runs the night before in an 11–0 loss to the Arizona Diamondbacks.

[1] He was the Giants' nominee for the Hutch Award, given annually to a player who perseveres through adversity, though Mark Teahen was the eventual winner.

[1][20] Martinez attended spring training with the Giants in 2010, but right elbow inflammation limited him to one game, and he was optioned to Fresno on March 23.

[24] The Giants elected to use top prospect Madison Bumgarner the next time Wellemeyer's turn in the rotation came around, and Martinez was moved to the bullpen.

As a member of the team that season, he received a ceremonial World Series ring, which he had to pick up from a FedEx distribution center in New Jersey.

[1] In nine games (one start) combined between San Francisco and Pittsburgh, he had an 0–1 record, a 4.12 ERA, nine strikeouts, nine walks, and 26 hits allowed in 19+2⁄3 innings.

On April 24, he and fellow pitcher Mike Zagurski were recalled to Arizona as Joe Paterson was sent to the minor leagues and Jonathan Albaladejo was designated for assignment.

[35] Fox Sports suggested that the Diamondbacks intended to use him as a long reliever, as Wade Miley, who had previously filled the role, was now making starts.

[36] Martinez made his lone MLB appearance of the year on April 25, giving up one run in the final inning of a 7–2 loss to the Philadelphia Phillies.

[34] Martinez re-signed with the Cleveland Indians on December 14, 2012, on a minor league contract that included an invitation to spring training.

"He really clutched up...that's not the easiest situation to be put into," manager Terry Francona said of Martinez's entering a tied game for his first MLB appearance in over a year.

[34] He lost all three starts that he made for the Salt Lake Bees of the Pacific Coast League, posting a 16.36 ERA before announcing his retirement on April 21.

[7] In 21 games (six starts) over parts of four MLB seasons, Martinez posted a 4–3 record, a 5.82 ERA, 32 strikeouts, 21 walks, and 78 hits allowed in 55+2⁄3 innings.

He worked as a financial advisor after leaving baseball and declined his acceptance into the Master of Business Administration program at Columbia University in favor of a job at PricewaterhouseCoopers.