PHILADELPHIA -- Spencer Howard is going to embrace this opportunity.

Howard will be pitching in a pennant race in September, meaning that people will be counting on the 24-year-old rookie right-hander to pick up big outs in big games as the Phillies pursue their first postseason berth since 2011. The front office guaranteed that on Monday, when it made one more addition to its bullpen before the Trade Deadline. No upgrades to the rotation solidified Howard’s spot as the No. 5 starter.

“It’s exciting,” Howard said following Monday night’s 8-6 victory over the Nationals at Citizens Bank Park, which improved the Phils to 15-15. “I like pitching in games that feel like they matter more. Games late in the season and playoffs and all that stuff are pretty fun. I’m excited to get there and see what the atmosphere is like.”

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Howard allowed two runs on five hits and two walks in five innings. He struck out four, including Nats stars Trea Turner and Juan Soto to start the game.

Howard earned the first win of his career, and he is now 1-1 with a 5.40 ERA after four starts. He leaned heavily on his four-seam fastball and slider in his first three outings, throwing those pitches a combined 80.2 percent of the time. On Monday, he mixed his fastball (52 percent), slider (21 percent), changeup (20 percent) and curveball (8 percent) more effectively.

It caught Joe Girardi's eye.

“I saw his whole repertoire,” the manager said. “He was not using it [before]. It’s not unusual for a young player not be comfortable right away and to kind of feel your way through some starts. I remember as a catcher. It’s nerve wracking. It’s hard when you’re out there and ... you’re trying to establish yourself. I hope today is just a big step for him, that he understands that he can really compete at this level and he can use all his pitches and have success.”

Howard is the No. 35 prospect in baseball, according to MLB Pipeline. His start on Aug. 9 against Atlanta was the most highly anticipated debut by a Phillies prospect since Aaron Nola in 2015 or maybe even Cole Hamels in '06.

Several pitching prospects within MLB Pipeline's Top 100 list have started games this season. The results are mixed: Casey Mize (No. 8) is 0-1 with a 6.75 ERA in three starts with the Tigers; Nate Pearson (No. 9) is 0-0 with a 6.61 ERA in four starts with the Blue Jays; Jesús Luzardo (No. 13) is 2-1 with a 3.71 ERA in seven appearances (five starts) with the A’s; Sixto Sánchez (No. 24) is 1-0 with a 2.25 ERA in two starts with the Marlins; Ian Anderson (No. 41) is 1-0 with a 1.50 ERA in one start with the Braves; Brady Singer (No. 61) is 1-3 with a 5.19 ERA in seven starts with the Royals; and Deivi Garcia (No. 99) pitched six scoreless innings in one start with the Yankees.

Perhaps Howard will be able to get into a rhythm with more regular work. He last pitched on Aug. 20.

“It’s been a while since he pitched,” said Rhys Hoskins, who stayed hot on Monday with a three-RBI night. “He’d probably tell you that there was a little bit of nerves, a little anxious the first couple starts. But I think you could tell today that he was a little more settled in. He left the stuff do the talking, right? Especially the first inning, striking the side out against three really good hitters. It was like, ‘OK, here we go. I can pitch here. I belong here.’ That goes a long way. ... We’re going to ask him to pitch in some big games, and we have nothing but confidence in him.”

The Phillies took a 1-0 lead in the first inning with Hoskins’ solo home run to left field, as he has now homered in three consecutive games. The first baseman is batting .379 (11-for-29) with five homers, 11 RBIs and a 1.455 OPS in his last seven games.

Jay Bruce homered in the second inning in his first plate appearance back from the 10-day injured list. Jean Segura’s double to left-center field in the fourth cleared the bases to hand the Phillies a 5-0 lead. Alec Bohm’s sacrifice fly made it 6-0.

But the night was Howard’s. He got back to his locker to find text messages from family and friends. His teammates doused him with beer and baby powder in the shower.

“I haven’t really felt it really click yet,” Howard said. “I think my goal is keep getting a little better every day. I think this is definitely an improvement on my last few starts. I’m going to keep working and see where it will take me.”