Arrieta (hamstring) was reinstated from the 10-day injured list prior to Friday's start against the Astros, Jeff Sanders of The San Diego Union-Tribune reports.
Arrieta suffered a hamstring strain in his Padres debut Aug. 18, but he'll be back in action following an absence of just over two weeks. The right-hander has struggled across his last five starts and has posted a 13.76 ERA and 2.71 WHIP in 17 innings.