Flores, who averaged 92.9 mph on his fastball last season, touched 99 mph in Grapefruit League play Thursday, Evan Petzold of the Detroit Free Press reports.
Flores got a swinging strikeout on the pitch, and a sustained increase in velocity would be good news for the young righty. He was selected to the 40-man roster in November, and while he'll likely start the year with Triple-A Toledo, Flores could be a bullpen option at some point in 2024 if he's able to pitch well in the minors.