SAN FRANCISCO -- Merrill Kelly was dominant for seven innings, Joe Mantiply worked a scoreless eighth and closer Ian Kennedy was on the mound in the ninth inning Tuesday night, holding a one-run lead.

It was set up to be a big win for the D-backs, especially when Kennedy retired the first two hitters of the ninth and then jumped ahead of Thairo Estrada 1-2.

Kennedy uncorked a 93 mph fastball to Estrada, who took the pitch, and home-plate umpire Cory Blaser started to rock back on his heels as if he were going to call a game-ending third strike.

Blaser instead ruled the pitch was a ball, and though he would later be shown to be correct by Statcast pitch data, the D-backs bench reacted to what they thought was going to be a third strike call and began barking at Blaser.

Their collective temperatures rose further when on the very next pitch, Estrada drove a ball off the right-field wall for a triple.

D-backs bench coach Jeff Banister got ejected by Blaser after he continued to yell from the dugout after the triple.

Kennedy then set to work on Giants veteran Brandon Crawford, getting him to swing through a fastball. On the next pitch, Kennedy threw another fastball and this time Crawford deposited it over the wall in center for a 2-1 walk-off win.

D-backs manager Torey Lovullo screamed at Blaser as the umpires walked off the field, earning a postgame ejection, but by the time he met with the media postgame he was aware that the pitch had indeed been called correctly.

"Officially it was a ball," Lovullo said. "I think what threw everybody off was the umpire kind of staggered and leaned back like he was going to ring him up. And we look at habits and body language and we thought he was going to get it, but he didn't. And you have to give the Giants credit. They didn't shut down and two big base hits later, they won a baseball game."

Kennedy, for his part, shouldered the responsibility.

"It was pretty close, but you can play victim all the time, [and] I still had another batter to face," Kennedy said. "It just sucks. I feel bad for Merrill who worked his butt off all game, the whole team, Joe, everyone that pitched before you. You just want to do your job. It's the worst way to end the game."

The ending overshadowed Kelly's performance, but it shouldn't because the right-hander was once again outstanding. In his last nine starts he is 4-0 with a 1.64 ERA.

What made Kelly's performance even more impressive is that the Giants have now seen him four times in the last seven weeks. In those games he has a 1.27 ERA.

Before the game, Giants manager Gabe Kapler laid out why Kelly has been such a challenge for his team.

"He has really good command," Kapler said. "He can put the baseball where he wants to put it. He’s got a quality changeup that makes it more difficult for lefties. He’s had, at the very least, even splits. You could probably make the case that he’s been pretty good against lefties as well. He’s a challenge for lefties and righties.

"We haven’t really solved the riddle yet. He’s been on the corners against us and hasn’t missed much in the middle of the plate. When he has, we’ve missed those or fouled them back. I think we really have to hone in in the middle part of the plate and be especially disciplined on anything that’s not in that middle part of the zone because he’s pretty good at staying off barrels."