The San Francisco Giants are on the verge of pulling the plug on No. 5 starter Todd Wellemeyer.

They’re not ready to recall 20-year-old Madison Bumgarner or to bring right-hander Joe Martinez back to the big club. The organization is reportedly set to call right-hander Eric Hacker, 27, up from Triple-A Fresno to take Wellemeyer’s scheduled start on Tuesday against the Washington Nationals.

The Giants could skip the fifth spot in the rotation and use Tim Lincecum on Tuesday, thus pushing back the next start for the No. 5 starter to May 29 against visiting Arizona.

As was suggested here on Wednesday night, the Giants are unwilling to rush Bumgarner to San Francisco after he has finally shown signs of regaining the form that earned him starting assignments in the big league playoff race in 2010.

Hacker has been the most effective Fresno starter. He’s 7-1 with a 2.20 ERA. The righty has 38 strikeouts and 12 bases on balls in 45 innings for Fresno.

He has the numbers to earn a spot in the big leagues, but he’s a 27-year-old who was drafted by the New York Yankees and bounced around the minor leagues since 2002.

Hacker is pitched three games for the Pittsburgh Pirates in 2009, working three innings in three relief appearances. That’s the extent of his big league experience.

Hacker’s career minor league statistics are virtually identical to those of Joe Martinez, who became very familiar to San Francisco fans during his time with the big club in 2009.

Martinez is 39-20 with a 3.51 ERA and Hacker 36-22, with a 3.19 ERA, in the minor leagues. Martinez has worked 592 innings, averaging 7.4 strikeouts and 1.9 bases on balls per nine innings. Hacker 531 innings with an average of 2.5 walks and 6.5 strikeouts per nine innings. Martinez has a minor league WHIP of 1.18 and Hacker a 1.27 WHIP.

Martinez, like Hacker, is 27.

Wellemeyer is 2-5 with a 5.71 ERA in seven starts for the Giants. He has walked 27 and yielded 33 hits in 41 innings.

(Hacker and Martinez statistical comparison provided by thebaseballcube.com. )

Ted Sillanpaa is a Northern California sports writer and columnist. Contact him at tsillanpaa1956@gmail.com

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