Yarbrough will serve as the Rays' primary pitcher out of the bullpen in Monday's game against the Rockies, Rodney Page of the Tampa Bay Times reports.
As he often did throughout the 2018 campaign, Yarbrough will enter the game after Ryne Stanek, who is expected to cover an inning or two as the opener before departing. Yarbrough covered four innings in his final exhibition appearance, so that probably represents the lower end of what kind of workload he'll receive in his 2019 regular-season debut.