"The Giants lost the lead in the seventh inning, reclaimed it, tacked on a run in the eighth, tapped Brian Wilson for a five-out save and kept 38,735 fans chewing their fingernails to the very last out of a 9-7 victory over the Arizona Diamondbacks on Sunday afternoon.

But the most important development came much, much earlier. Long before the Giants scrapped late to avoid a sweep, Matt Cain ensured they would have a fighting chance.

Cain defused what looked to be another incendiary first inning, breaking the rotation's dispiriting pattern and possibly helping the entire team turn a rather gruesome page.

The Diamondbacks had two runners in scoring position before Cain recorded an out, but he rebounded by striking out the side. It was an important escape for the Giants staff, which had allowed 13 first-inning runs over the previous three games. Barry Zito, Tim Lincecum and Madison Bumgarner had taken turns getting blitzed out of the gate.

Instead, Cain pitched effectively into the seventh inning and departed with a 5-2 lead. He turned in just the second quality start in the club's past eight games -- and he owns the other one, too.

"If I could figure out a way to call the scorer and transfer my win, I would," said left-hander Jeremy Affeldt, who ended up with the decision after allowing Adam LaRoche's two-run double that gave Arizona a one-run lead in the seventh."