Griffin is slated to start Thursday's game against the Mets in Cleveland, Nate Ulrich of the Akron Beacon Journal reports.
Acquired from the Nationals on Monday, Griffin will make his Guardians debut three days later after getting some time to acclimate to his new team. After spending the previous three seasons pitching in Japan before signing a one-year, $5.5 million deal with the Nationals in December, Griffin has emerged as an unlikely All-Star in his return to affiliated ball. While leaning on a seven-pitch mix, Griffin turned in a 12-3 record, 3.06 ERA, 1.07 WHIP and 116:30 K:BB in 129.1 innings over his 22 starts with Washington. Though he's vastly outperformed his peripherals (4.09 FIP, 4.10 xERA, 3.80 SIERA), Griffin's change in home park from one of baseball's more hitter-friendly venues in Nationals Park to a more neutral environment in Progressive Field could help him stave off regression.