SAN FRANCISCO -- Buster Posey’s decision to sit out the pandemic-shortened 2020 campaign accelerated top catching prospect Joey Bart’s arrival to the Majors last summer, but Posey’s return created few opportunities for Bart to impact the Giants this season.

With Posey on the injured list and Curt Casali needing a day off following a night game, Bart finally got a chance to contribute on Saturday afternoon, going 2-for-5 with an RBI and catching Anthony DeSclafani’s gem in a 10-4 rout of the Nationals that clinched a series victory at Oracle Park.

“It was fun,” Bart said. “I was really trying to lock in with DeSclafani and get him on his game and trying to get us on the same page. That went pretty well. Anything else that happened at the plate was just extra. I’m glad I found a few holes there and was able to get on base a few times.”

DeSclafani struck out six and allowed only three hits over six scoreless innings to end his first half with a career-high 10 victories and a 2.68 ERA over 18 starts. He received ample run support from the Giants, who rapped out 14 hits and chased Nationals left-hander Jon Lester in the third inning.

Thairo Estrada collected four hits, including a pair of swinging bunts, to lift his batting average to .360 over 12 games, and Brandon Crawford chipped in with three more, including his 18th home run of the year in the sixth inning. Crawford, who earned his third career All-Star selection this year, is only three homers shy of matching his career high of 21 with one game remaining in the first half.

At 56-32, the Giants are now guaranteed to head into the All-Star break in first place after increasing their lead in the National League West to 2 1/2 games over the Dodgers, who were scheduled to face the D-backs on Saturday night.

“It’s awesome,” DeSclafani said. “It’s so much fun to be a part of this team. It’s such a great group of guys. Everyone just seems selfless. It’s just fun coming to the ballpark.”

Bart, 24, made his first start of the season after being recalled from Triple-A Sacramento prior to Saturday’s game. The Giants’ No. 2 prospect replaced right-hander Logan Webb, who was optioned after working three scoreless innings in a 5-3 win over the Nationals on Friday night. San Francisco won’t need a fifth starter until July 20, giving Webb an opportunity to continue to build up his arm over the All-Star break.

The Giants decided to use the open spot on their roster to take another look at Bart, who is batting .338 with a .981 OPS and eight home runs over 35 games with Triple-A Sacramento this season. Bart struggled after making the jump from Double-A to the Majors last year, batting only .233 with a .609 OPS and zero home runs over 33 games, but president of baseball operations Farhan Zaidi said the Giants have been pleased with the strides they’ve seen him take at the plate this year.

“The performance against right-handed pitching in particular has been really good,” Zaidi said Friday. “He’s actually hit righties better than lefties, which is something that we’ve been looking for. The walk rate and strikeout rate don’t jump off the page, but I think the at-bat quality has been better. He’s been really consistent and really good defensively as well. We’re really happy with his progress.”

Bart batted seventh against Lester and helped extend the Giants’ three-run rally in the first inning by reaching on an infield single that came off his bat at 102.2 mph. Bart later blooped an RBI single to right-center field as part of the Giants’ five-spot in the third. His latest stint in the Majors could prove brief, as Posey is hoping to return for the second-half opener in St. Louis on July 16, but the Giants continue to think highly of Bart, the No. 2 overall pick of the 2018 Draft.

“There are no concerns about his ability to impact and drive the baseball,” manager Gabe Kapler said before the game. “I think there’s enough aptitude in there where some of the holes that he had last year have started to get smaller. I think he’s a better hitter now than he was when we had him in the summer last year. I think he’s a better all-around player, and I think those improvements speak to the type of baseball player that he can be for us, which is kind of an excellent middle-of-the order, regular bat if he continues to improve.”

The Giants carried a 9-0 lead into the seventh inning before the Nationals finally got on the board against right-hander Tyler Beede, who gave up three runs over one inning in his first Major League appearance since Sept. 26, 2019. San Francisco added Beede to its roster earlier this week after he completed his rehab from March 2020 Tommy John surgery.

“I’m glad that he came out of the game healthy and he got back on a Major League mound,” Kapler said. “I think that’s a positive. I think Tyler knows this, but he’s going to need to be ahead in counts, and he’s going to need to throw more strikes.”