Beltre appeared as the designated hitter in Tuesday night's 11-3 loss.
"Adrian was in some discomfort but pushed through it," Daniels said. "We're going to get some tests. It's more than a stomach ache. It's some sort of abdominal discomfort. Hopefully, it's not significant."
Daniels indicated that it is not in the same area as the burst appendix earlier in Beltre's career with the Dodgers that required two surgeries to repair.
Tanner Scheppers, the young right-hander who hit a batter and threw a wild pitch during the eight-run fourth inning on Monday night, sustained no structural damage in his knee, Daniels reported.
Scheppers, 25, had a clean X-ray of the knee, and an MRI later in the day confirmed that there is no structural damage. He is listed as day to day.
Scheppers was involved in a home-plate collision with Angels catcher Chris Iannetta following his wild pitch to Torii Hunter with the bases loaded. Scheppers was waiting for the throw from catcher Mike Napoli when he was upended by Iannetta. While the pitcher was on the ground writhing in pain, Mike Trout also scored from second, sliding into Scheppers.
"There was just a real quick, sharp pain in the [right] knee," Scheppers said. "He kind of lifted me a little bit. I was standing on the plate, and he kind of got my knee and I fell right on top of [the plate].
"I feel like nothing is structurally wrong. I wouldn't be able to put as much pressure on it as I am."
The initial report on Hamilton had been that his vision problem was connected to a sinus condition. Daniels said his exam did not indicate that was the case.
"It was a quick read," Daniels said of the sinus report. "There are issues with his vision and focus. Seeing a doctor earlier today, there isn't any indication that it's a sinus condition.
"The way [Hamilton] described it was more trouble with focus than blurred vision. It's hard to send a guy up to the plate against a guy throwing 95 [mph] and not seeing it properly."