PHILADELPHIA (Interstat) — Derek Hill launched a tie-breaking grand slam in the seventh inning and Bryce Harper added a two-run homer in the eighth as the Philadelphia Phillies rallied past the Washington Nationals 6-3 on Monday night at Citizens Bank Park.

The Nationals took an early command behind an efficient start from left-hander Andrew Alvarez, but the Phillies broke through with a four-run seventh that flipped the game in their favor. Hill’s blast to left-center came with the bases loaded and erased Washington’s three-run lead, giving Philadelphia its first advantage of the night. Harper’s home run to center later provided valuable insurance as the Phillies won for the sixth time in their last seven games.

Washington struck first in the opening inning when Abimelec Ortiz homered to right field off Phillies starter Aaron Nola. The solo shot was Ortiz’s first of the season and gave the Nationals an early edge. Nola settled in after that, allowing only one more run over his six innings, but the damage continued in the second. Keibert Ruiz singled sharply to right and Daylen Lile followed with a two-run homer to right-center, extending Washington’s lead to 3-0. Lile’s blast, his 14th of the year, scored Ruiz and gave the Nationals a comfortable cushion.

Alvarez, meanwhile, was sharp through the opening frames. He allowed just three hits and two earned runs over 6 1/3 innings, striking out five while keeping the Phillies off the board through six. Philadelphia managed only a single each from Alec Bohm and Bryson Stott in the early innings, with both threats extinguished by double plays. The Nationals defense turned two twin killings behind Alvarez, and the left-hander repeatedly worked out of trouble.

The Phillies finally broke through in the seventh. Alvarez began the inning by getting Bohm to fly out, but Bryan De La Cruz was hit by a pitch and Bryson Stott walked. Eddy Yean relieved Alvarez and promptly walked Edmundo Sosa to load the bases. Hill then worked a 2-1 count before driving a pitch to left-center for his ninth home run of the season, a grand slam that cleared the bases and put the Phillies ahead 4-3. The home crowd of 41,115 erupted as Hill rounded the bases, and the Phillies had their first lead of the night.

Philadelphia added to its advantage in the eighth. Kyle Schwarber walked with one out, and pinch-runner Justin Crawford advanced on a pickoff attempt before scoring when Harper homered to center. The two-run shot, Harper’s 24th of the season, gave the Phillies a 6-3 lead and provided a comfortable margin for the bullpen.

Kyle Backhus earned the win with a scoreless inning of relief, his second decision of the season. He entered in the seventh after the Nationals had put a runner on third with one out, and he escaped the jam by inducing a fielder’s choice at home and a foul-tip strikeout. Backhus improved to 2-1 with a strikeout in his one inning of work. Orion Kerkering and Jhoan Duran each pitched a perfect inning to close out the game, with Duran striking out two in the ninth to secure his 25th save.

Tom Cosgrove took the loss for Washington, allowing the go-ahead runs in the seventh without recording an out. He was charged with his first decision of the season, dropping to 0-1. The Nationals saw their losing streak reach five games, while the Phillies moved to 60-53 on the year. Washington fell to 55-59.

The Nationals had several offensive bright spots despite the loss. Ortiz, who finished 1-for-3, provided the early spark with his first-inning homer. Lile went 1-for-4 with the two-run shot and two RBIs, giving him 14 long balls on the season. Ruiz collected two hits, including a sharp single in the second and another in the sixth. James Wood also singled in the third, but Washington managed only six hits overall and struck out 10 times.

Nola, despite allowing three runs on six hits over six innings, kept the Phillies within striking distance. He struck out five without walking a batter, and his ability to limit damage after the second inning gave Philadelphia’s offense time to rally. Nola retired the side in order in the fourth and worked around a double-play ball in the fifth to keep the score at 3-0.

The Phillies had only five hits in the game, but they were opportunistic. Hill’s grand slam was the key blow, while Harper’s homer accounted for two more runs. Bohm and Stott each singled, and Sosa added a base hit in the fifth. Philadelphia also drew four walks and benefited from two hit batters, helping to manufacture runs without a sustained offensive attack.

Washington threatened in the seventh before Backhus entered. Nasim Nuñez reached on a throwing error by the pitcher and moved to third on a fielder’s choice. Brady House then reached on a fielder’s choice that cut down Nuñez at the plate, and Jacob Young walked to put two runners on. But Backhus induced a groundout to first and struck out Andrés Chaparro on a foul tip to end the inning.

The Nationals had another chance in the ninth against Duran, but the closer was dominant. Daylen Lile grounded out to first, Nasim Nuñez struck out swinging, and Brady House was hit by a pitch before Jacob Young was called out on strikes to end the game. Duran earned his 25th save in flawless fashion, striking out two over a scoreless inning.

The game took 2 hours and 38 minutes. Citizens Bank Park hosted the matchup with an attendance of 41,115.

The victory was Philadelphia’s second consecutive win and improved its record in the season series against Washington to 3-2, with three more games scheduled in this four-game set starting Tuesday. The Nationals, who dropped their fifth straight, will look to rebound in the same ballpark.

Interstat’s game simulator had projected a final score of Washington Nationals 4, Philadelphia Phillies 3. Interstat’s ELO system had projected Philadelphia with a 62.70 percent probability to win. Philadelphia had been installed as a pregame favorite with a spread of -1.5. The total score of 9 went over the over/under line of 9.5.