PHOENIX -- These are the types of games that keep Torey Lovullo up at night.

The D-backs manager doesn't like to lose, period, but losing games because of sloppy defense … that takes it to a different level.

"We talk about winning the inch," Lovullo said. "We talk about doing the little things and prepping and understanding and getting the play made. This is the type of game that really bothers me, because that's not Arizona Diamondback baseball. We don't do that stuff here."

The play that will jump out the most from the D-backs' 6-5 loss to the Giants on Friday night came in the top of the ninth inning.

With the game tied at 5, reliever Caleb Smith retired the first two hitters of the inning before Mike Yastrzemski singled to center. Evan Longoria followed with a grounder to Sergio Alcántara at third. Alcántara fielded the ball cleanly, but his throw to second to force out Yastrzemski was in the dirt and got by second baseman Ketel Marte.

Instead of being out of the inning, Smith had to face J.D. Davis, who lined a ball into the left-field corner to score Yastrzemski with what proved to be the winning run.

"The runner at first base, he's a really good runner," Alcántara said. "By the time I looked up, he was already close to second base so I kind of rushed my throw there, and that was essentially what happened."

Alcántara got the start at third Friday in part because Josh Rojas, who has started the bulk of the games there this year, has seen his playing time cut after suffering some defensive lapses, the last of which came in Tuesday's doubleheader against the Dodgers.

"He might have been a little bit surprised by the break of the runner at first base, picked his head up and then rushed the throw," Lovullo said. "His footwork did not look 'Serge like.' It looked like he had to speed some things up. So in my opinion, with Longoria running he should have just taken his time, reorganized his feet and drove the throw across the diamond. He's an extremely accurate thrower. I just think he tried to make a hustle play, and to me that's more of a mental error than a physical error because you can reload and make the play."

Before meeting with the media, Lovullo had already started talking to his coaches about what had transpired.

Saturday, after no doubt a tough night of sleep, Lovullo will circle back with his coaches and come up with a plan to address the mistake going forward. Then the individual coaches will take up anything that needs correcting with the player involved.

"That's how we do it," Lovullo said. "We talk about it, go over with the coaches, be prepared to answer any questions, deliver messages, be prepared to answer why. And the player should be prepared to answer why, too. We don't miss these opportunities. We make mistakes. We coach it up. We got to find a way to execute and get the job done. That's the bottom line. We've got to improve. We've got to get better. There's identifiable things that we've got to continue to teach and grind through."