Red Sox closer Kenley Jansen was originally scheduled to pitch Monday against the Twins, but he was scratched due to lower back tightness, the club announced shortly before first pitch.

Jansen may pitch Tuesday at home against Tampa Bay instead, and the 36-year-old is still expected to be ready and available for Opening Day, the club said.

Still, the apparent setback is cause for concern.

Though the Red Sox said from the outset that Jansen wouldn’t need much game action to prepare for the season, he has so far only made one appearance in a Grapefruit League game. Jansen’s debut was delayed by lat soreness that developed early in camp, and once he finally got on the mound last Friday against Minnesota he got hammered for three runs on two home runs over 0.2 innings.

Red Sox manager Alex Cora said early in the spring that a veteran like Jansen should only need five innings to prepare for the season, and if Jansen can get back on the mound Tuesday it might still be possible for him to do that over the final week and a half of camp.