Derek Shelton’s anxiety was running high during a rain delay Saturday night, as the Pittsburgh Pirates manager sat in his office and watched the downpour and the clock as it ticked past the one-hour mark. Shelton realized that the longer the delay lasted, the less chance he would be able to send Mitch Keller back onto the mound. Keller was as sharp as he’s been through the first four innings, and this wasn’t a game the Pirates wanted to turn over to their bullpen so early. Keller did not return, but after the Arizona Diamondbacks tied the game, Bryan Reynolds blew it open with a two-run home run and Joey Bart added an RBI single in a three-run sixth inning before the bullpen closed out a 4-2 win Saturday night before 35,515 at PNC Park. The Pirates (56-54) pulled even in the three-game series with the Diamondbacks (59-52), who held a 3½-game lead in NL wild-card standings and beat them 9-8 on Friday night. All-Star rookie right-hander Paul Skenes (6-1, 1.90 ERA) will start for the Pirates on Sunday as they attempt to win the series. Bart blasted lefty Jordan Montgomery’s full-count sinker 418 feet to the left field bleachers for his eighth home run and a 1-0 lead in the second inning. Keller kept the Diamondbacks scoreless through four innings, allowing one hit and two walks with four strikeouts while throwing 44 of his 60 pitches for strikes before a 68-minute rain delay. "Mitch was really good,” Shelton said. "I mean, it was unfortunate. I thought he was really sharp. He had just about everything working. I mean, it kept raining, I kept sitting in my office hoping it would stop.” After the delay, the Diamondbacks took advantage of Keller’s absence. They pounced on Pirates righty Dennis Santana, who surrendered back-to-back singles to Eugenio Suarez and Gabriel Moreno, then hit Geraldo Perdomo to load the bases with no outs. The Pirates turned to Jalen Beeks, and Shelton called it a "huge” performance from the lefty acquired Tuesday from Colorado. Beeks got Corbin Carroll to pop up to short and Ketel Marte swinging at an inside fastball before battling Joc Pederson in a nine-pitch at-bat. After driving successive 3-2 fastballs just wide of the right field foul pole, Pederson drew a walk to score Eugenio Suarez and tie it at 1-1. That brought to the plate the former Pirates first baseman Josh Bell, who homered twice Friday in his Arizona debut after being acquired from Miami at the trade deadline. Beeks didn’t throw a pitch inside the strike zone, getting Bell to chase changeups in the dirt and outside before going down swinging at a high heater to escape with limited damage. "That was big time,” said Pirates reliever Kyle Nicolas (2-2), who pitched scoreless sixth and seventh innings to earn the win. "It was cool seeing a guy, a new guy, coming in a spot like that and being able to limit them to one run. That was probably the main reason we won tonight. He deserves a lot of credit there. That’s not an easy to be put in. He made the best of it.” Andrew McCutchen started the sixth by working an 11-pitch at-bat before smacking a single to left field, but it came at a cost. McCutchen winced as he broke out of the batter’s box, then rubbed his left leg and was removed from the game as a precaution with left quad tightness. After Ji Hwan Bae replaced McCutchen as pinch runner, Reynolds crushed Cecconi’s full-count fastball 405 feet to center field for his 19th homer to give the Pirates a 3-1 lead. "He doesn’t let the moment get big for him,” Shelton said. "I mean, he’s our best player. And he exemplifies that every night the way he plays. When he gets hot, you’re right, he can carry us for bits.” Connor Joe followed with a high fly ball that dropped in left but was called out on Lourdes Gurriel’s throw to second base. The Pirates challenged the call and it was overturned after a video review, giving Joe a double and allowing him to score on Bart’s flare to left to make it 4-1. "Joey’s base hit not only gets us to three,” Shelton said, "but it changes the whole complexion of how you use your bullpen over the last two innings.” The Pirates then got scoreless pitching performances from Nicolas and Aroldis Chapman, who had three strikeouts in the eighth. It got tense in the ninth when closer David Bednar struck out Suarez and Moreno before giving up a double to Perdomo and walking Carroll. Marte sliced a single to right to score Perdomo to cut the Diamondbacks’ deficit to two runs before Bednar got pinch hitter Alek Thomas to fly out to center to earn his 20th save. "This is the type of game we want to be playing every single night,” Keller said. "Every single game matters. Every team we play matters. It’s a lot more fun than the other version of that.” Kevin Gorman is a TribLive reporter covering the Pirates. A Baldwin native and Penn State graduate, he joined the Trib in 1999 and has covered high school sports, Pitt football and basketball and was a sports columnist for 10 years. He can be reached at kgorman@triblive.com. Remove the ads from your TribLIVE reading experience but still support the journalists who create the content with TribLIVE Ad-Free. Get Ad-Free > Sign Up for NotificationsStay up-to-date on important news from TribLIVE