SAN DIEGO -- Austin Hedges has made quite the impact behind the plate this season. At the plate? He’d hardly made an impact at all.

Until Friday night, that is.

With two outs in the ninth, Hedges turned around a 2-1 fastball from Nationals closer Sean Doolittle, lofting it into shallow left field for his first career walk-off hit. The light-hitting Padres catcher had delivered at the game’s biggest moment, sending the Padres to a thrilling 5-4 victory.

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“Too good to be true,” said Hedges, still reveling in the postgame celebrations, which had spilled from the Petco Park playing field into the Padres’ clubhouse.

“I just got beat,” said Doolittle.

Indeed, almost all of Hedges’ value this season has been derived from his play behind the plate. He’s regarded as arguably the game’s best defensive catcher, and the Padres’ Major League-youngest pitching staff raves about the work he does on opposing hitters.

“It can’t be overstated how much he brings to the table,” said left-hander Nick Margevicius, who worked 3 2/3 scoreless frames Friday night. “He handles the staff with such a presence. Having him back there, knowing he’s done all of his homework ... he’s so important to our success.”

That may be true. But Hedges’ bat has lagged well behind. He entered play Friday night hitting .188 with a .593 OPS. Sure, the Padres love what Hedges is doing defensively, but they could use a bit of production on offense to go along with it.

In that regard, Hedges is hopeful that Friday could mark something of a turning point. His bat came on strong during the second half last season, after all.

“I've got a lot of confidence in myself,” Hedges said. “And we've got a lot of season left.”

Strangely enough, Hedges felt as though he was atoning for what he deemed to be a defensive miscue. The Nationals took the lead in the top of the ninth inning when Adam Warren’s slider scooted by Hedges, allowing the go-ahead run to score.

(Never mind that Hedges seemed to have little chance on a wild pitch that wasn’t even close to its intended target.)

“I was really disappointed not blocking that ball in that last inning, allowing that run,” Hedges said. “I expect way more out of myself in that situation. I was just praying in the dugout. … I just wanted to win that game.”

A few minutes later, he’d get the chance to do so himself. And he made it count.

Tough as Nayls

It was rookie Josh Naylor who made Hedges’ moment possible. The Nationals were still in business after Warren’s wild pitch, but Naylor prevented any further damage with a brilliant assist from left field to double up Yan Gomes at third base.

Then, with two outs in the bottom of the ninth, Doolittle went upstairs with a first-pitch fastball. Naylor turned on it and shot an RBI single up the middle, tying the game.

“I was just thinking, ‘Choke up a bit, get something good to hit,’” Naylor said.

“He's got the kind of bat speed that can get to anybody's fastball,” Green said.

Naylor swiped second base on the very next pitch for his first career steal, which set the stage for Hedges’ heroics.

An outfield assist, a game-tying single and a pivotal stolen base -- quite the inning for the 21-year-old left fielder.

What can’t he do?

Fernando Tatis Jr. is making up for lost time. Since he returned from a left hamstring strain on Thursday, the Padres’ rookie shortstop hasn't stopped hitting. He went 3-for-4 on Friday night.

There are dozens of different ways the 20-year-old phenom can impact a ballgame. In his first three at-bats, he showed off three of them.

In the first, Tatis hit an opposite-field single -- a 111-mph rocket on a pitch just off the outside corner. In the third, he sent a grounder toward third base, and his wheels carried him to an infield hit. In the sixth, he crushed a two-run homer to straightaway center.

They said he was a five-tool player. They weren’t kidding.

“He’s special,” Green said.

“At one point, he was going to single-handedly win the game for us,” Hedges said. “It’s unreal.”

First Tatis, then Naylor. The Padres’ top-ranked farm system is clearly starting to pay dividends.

“What fires me up the most is seeing how they handle the big situations,” said Eric Hosmer, who tripled, then scored on Naylor’s single. “It can be hard for a young guy not to overswing. These guys have an ability to just lock in. ... These guys are playing well above their age.”

Miggy-backing

All season, the Padres have searched for an effective fifth starter. They put Margevicius and Miguel Diaz together on Friday night -- and they found one.

Margevicius, the starter, was sharp for 3 2/3 innings. But after he allowed a single to Howie Kendrick with two outs in the fourth, Andy Green sprang off the top step of the dugout with a quick hook.

The reasoning was simple enough. Margevicius has struggled mightily this season in his second and third trips through the lineup. Diaz -- a hard-throwing right-hander and Margevicius' polar opposite -- was available after returning from knee surgery earlier in the week.

Diaz piggybacked Margevicius with two scoreless frames, and the Padres carried a 3-0 lead into the seventh inning.

“We wanted to make sure the matchups favored us,” Green said. “They did, for the most part. We got what we wanted. Any time, you look at a starter -- or two guys -- and you're talking about getting through six innings of no-run ball, what else do you want? It doesn't matter how you get there. Whether it's one guy or two guys, we got to where we wanted to get to.”