DETROIT -- Astros starter Bud Norris remained sore on Tuesday after tweaking his back throwing warmup pitches prior to the sixth inning and exiting Monday night's game against the Tigers.
"It's pretty sore still," he said. "But [the trainers] said the next couple of days it will be painful."
As it stands, it's still uncertain if Norris, who was officially diagnosed with lower back spasms, will make his next scheduled start, which would likely come Sunday in the finale of a three-game series against Pittsburgh.
Norris classified his availability as "to be determined," but he also hopes to benefit from Thursday's off-day, meaning he will get five days' rest instead of the usual four before taking the hill.
Manager Bo Porter said it's a day-to-day injury, and the right-hander will continue to undergo treatment over the next few days.
"Whenever you're talking about back spasms, it's something that the next day is probably going to be worse than it was when it first happened," Porter said. "So he'll continue to get treatment, and hopefully the prognosis gets better each and every day."
Norris entered Monday with a 3.40 ERA, but after getting roughed up for seven runs in five innings, it rose to 4.32.
Anthony Odoardi is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.