The Nationals prospect took a no-hitter into the seventh en route to his 10th win Sunday as the Class A Hagerstown Suns beat the Drive, 7-2.
Grace (10-5) retired the first 14 batters he faced before walking Xander Bogaerts with two outs in the fifth. His no-hit bid ended with one out in the seventh when Brandon Jacobs bounced a ground-rule double over the left-field fence.
"I threw a changeup up and over the middle of the plate," Grace said. "I was trying to be aggressive and throw strikes."
The 22-year-old left-hander walked Christian Vazquez and, after Jacobs stole third, experienced cramping in his hip and was removed for precautionary reasons.
"It was frustrating to get taken out in that situation, but I understand it, especially on such a hot day," said Grace, who took to the mound with temperatures in the low 90s.
Wilson Eusebio relieved, but both inherited runners scored on an error by third baseman Blake Kelso. Grace was charged with a pair of unearned runs on one hit and two walks. He struck out three.
Selected by the Nationals in the eighth round of last year's Draft, Grace has not allowed an earned run over 12 1/3 innings in his last two starts. He has won three straight decisions and seven of his last eight to join Lakewood's David Buchanan as the only 10-game winners in the South Atlantic League.
Eusebio gave up two hits over 2 1/3 scoreless frames to earn his fifth save.
Michael Taylor went 2-for-3 with his 11th homer, a triple and three runs scored out of the ninth spot in the order for Hagerstown.
Greenville's Brandon Workman (2-6) lost his second straight start after yielding three runs on four hits over six innings. He struck out six and walked two.