Giants fans aren’t the only ones frustrated after the team’s nightmarish doubleheader Thursday in Philadelphia.Broadcaster Mike Krukow joined KNBR’s “The Murph & Markus Show” Friday morning to express his exasperation following the Giants’ pair of walk-off losses, results Krukow said were avoidable if not for crucial errors in pitch selection.“I’m not good at all,” Krukow told hosts Brian Murphy and Markus Boucher when asked how he was holding up after Thursday’s defeats. “I was screaming at the TV set yesterday, and [my wife] Jennifer is looking at me like I’m nuts. And then she comes over and…lo and behold, a couple minutes later she’s screaming at the TV. I think that was indicative of a lot of Giants fans yesterday, as to what they saw.“What was especially upsetting was they should have won both games. They outplayed the Phillies both ends of the doubleheader and they wind up with what the little bird left on the rock. That’s a frustrating day.”The Giants were one out away from victory in each game on Thursday but failed to secure either win as the bullpen...