The Lynchburg Hillcats got their first taste of Minor League Baseball’s new extra-inning rule this season.

They didn’t like it.

Potomac took advantage of MiLB’s rule of starting each half inning in extras with a runner at second by using a pair of line-drive singles to score the tying and winning runs in a 5-4 victory at Pftizner Stadium in Woodbridge.

Jake Noll’s single to center scored Carter Kieboom for the winning run, as all three Nationals batters in the 10th reached against Hillcats reliever Luiz Jimenez (1-1).

Blake Perkins started the inning on second and Kieboom drew a walk. Austin Davidson followed with an RBI single to center that scored Perkins and moved Kieboom to second.

Noll followed four pitches later with the walk-off single.

The Hillcats (7-7) scored in the top of the 10th thanks to a pair of fly balls to right field that allowed Luke Wakamatsu to eventually score on Li-Jen Chu’s sacrifice fly for a 4-3 advantage.

But that was all the ’Cats could do.

The Hillcats led 3-1 after Chu’s solo homer in the top of the sixth inning, but the P-Nats (9-6) took advantage of a Chu throwing error in the seventh to cut the deficit to one, and then Tres Barrera’s single in the eighth scored Kieboom to tie the game.

All three of the Hillcats’ errors came in the seventh and eighth innings.

The defensive meltdown ruined Tanner Tully’ quality start. The southpaw retired 12 in a row and pitched into the seventh inning.

He allowed two runs on six hits and struck out five.

Chu went 3 for 4 and Conner Capel went 2 for 5.

Barrera and Noll each had three hits for the P-Nats.

The four-game series continues at 7:05 p.m. today. Justin Garza (1-0, 0.00) is scheduled to start for the Hillcats against P-Nats starter Matthew Crownover (1-0, 3.12).