Max Scherzer, shown here Thursday, seems unlikely to make his scheduled start Tuesday. (Katherine Frey/The Washington Post)

MIAMI — Max Scherzer played catch briefly Sunday morning, on flat ground with strong velocity. That is the extent of the between-start work he has done since jamming his right thumb on Thursday. His thumb is still sore and still swollen, and he seems unlikely to make his scheduled start on Tuesday because of it.

Scherzer said he is “dealing with a little sprain in there,” the first time anyone has referred to the injury as anything more than the swelling that can result when a player swings and is jammed badly. He says the injury swelled up more Thursday night than he expected, and so the Nationals began aggressive treatment as soon as he arrived on Friday.

“I’m progressing every day. I’m literally day-to-day,” Scherzer said. “I’m making progress every single day from the treatments, doing the hot-cold contrast non-stop, so for me it’s just keep doing the treatments and see where this goes.”

Scherzer was scheduled to throw a bullpen session — 50 or so pitches off a mound most starters throw to tweak things between starts — on Saturday. Because of the swelling, he could not do that. Manager Matt Williams said he would evaluate Sunday whether or not he could do that a day late. He could not, opting for a light flat-ground session instead.

“Felt good, felt better than I thought it was gonna feel,” Scherzer said. “I was able to get more on the ball than I thought, so that was the encouraging sign. I just gotta keep progressing each day from here on out.”

He would not commit to making his start Tuesday, but said “I’m not ready to rule it out completely, but I also have to be honest with myself because any time you deal with an injury to your pitching hand, you literally have to be 100 percent to go back out there.”

Scherzer said he cut the middle finger on his right hand in college and tried to pitch through the issue. A few weeks later, he developed bicep tendinitis and “really almost messed up my shoulder.”

“Any type of discomfort is gonna alter the way I throw the ball. If I alter the way I throw the ball, I can really run the risk of major injury to my arm, so I really respect that I have to be at 100 percent,” Scherzer said. “That’ll be my test, if I can throw all my pitches on flat ground at 100 percent.”

As of Sunday, he could not. While he said he is improving daily, even hourly, and though he said he does not need to throw off a mound before making his next start, the 30-year-old seems to be opting for caution. If he is unable to make his next start, the Nationals can look to their bullpen, or perhaps to Syracuse, for fill-in options.

“”I don’t anticipate him missing more than one turn, but again, you don’t know,” Nationals Manager Matt Williams said. “He threw today, he played catch today, waasn’t fully comfortable with getting on a mound yet and going to work with all his pitches. So that being said, we’ll probably have to make an adjustment on Tuesday– we don’t know exactly who that is yet. We’ll get through tomorrow’s game and see where we’re at, but there are options for us. I don’t know if Max is gonna make this one.”

Tanner Roark has not thrown more than an inning since April 13, no more than two since the first week of the season. Therefore, he would likely be unable to go more than four innings, since he is not stretched out as he would be if he had been training as a starter. Starting Roark, then, would require a lot of work from an already beleaguered bullpen. Then again, Roark is an efficient worker who could likely gut out more innings.

If the Nationals look to Syracuse instead, they would likely choose between Taylor Jordan or A.J. Cole. Syracuse did not play Thursday, so no starter is directly on turn to pitch Tuesday. Jordan is scheduled to pitch Sunday, Cole Monday. Taylor Hill is the Chiefs’ scheduled Tuesday starter. He pitched last Wednesday.

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