Holmgren said X-rays of Bryzgalov's foot taken before and after Monday's game didn't show an injury; an MRI Tuesday revealed the fracture.
Holmgren added he didn't believe the injury was serious and that Bryzgalov could practice as soon as Friday.
"We're hoping that he'll be back on the ice practicing with the idea that he can play on the weekend," said Holmgren. "It's just going to be a little bit of pain management for Ilya.
"Obviously when you're dealing with something like this, it might be too painful to skate on Friday, but we'll see. He doesn't feel that bad today. We'll see how it is. It's not a thing that surgery is required; it's nothing like (James) van Riemsdyk's broken foot or anything like that. It's a chip off a weight-bearing bone, and the doctor has said it'll be absorbed back into his system, the little chip that's in there, and there's no real risk here at all. It's just he's in a little bit of pain right now.
"Ilya's a tough kid. He wants to play, and we look forward to seeing him on the ice with the team at practice on Friday."
Bryzgalov has been the best goalie in the League in March, going 10-2-1 in 13 games, with a 1.43 goals-against average, .947 save percentage and four shutouts. He was named NHL First Star of the Week for the first two weeks of March, and earlier this month set the club scoreless streak record of 249:43.
He also had a streak of 11 straight games allowing two goals or less snapped Monday when he allowed four goals in a 5-3 loss to Tampa Bay.
Holmgren said there never was a thought to pull Bryzgalov from the game Monday.
"Ilya wanted to play," said Holmgren. "To be honest with you, I knew what was going on. I watched the game and I didn't see any issues. The goals they scored were good goals. The last one he wasn't paying attention when Matt (Carle) had the bobble at the side of the net. The other goals were good goals that you can't really fault him on. I didn't have any issues with how he played the game and I don't think his foot was an issue during the game."
Bryzgalov had started 19 of the last 20 games; now Bobrovsky will be pressed into duty. Bobrovsky has played just one game in March, and hasn't won a game since Feb. 9.
The Flyers have six games left, and after Thursday they next play Saturday at home against Ottawa and Sunday in Pittsburgh.
"Ilya wants to play," said Holmgren. "He feels like he'll be OK, but we'll just see how it goes. I think we'll have a better grasp on how he is (Wednesday) ... and then probably more on Thursday and Friday. As I said, nobody's really concerned. The doctors are not concerned, (trainer) Jimmy McCrossin's not too concerned. He's a little sore right now."
The Flyers also announced that defenseman Kimmo Timonen will not play Thursday and is day-to-day due to an upper-body injury. The team recalled defenseman Marc-Andre Bourdon from Adirondack to replace him.
Holmgren said giving Timonen a game off is more of a maintenance issue than any injury, and part of a plan put in place following Timonen's five-game absence earlier this month due to an upper-body injury.
"When Kimmo missed the time earlier, it was kind of a planned thing where we wanted to give him some rest and do some rehab," said Holmgren. "This is also part of the plan. It's just take this day off, he doesn't have to fly up, he doesn't have to play the game. He can rest and rehab and get ready to play on the weekend."
In addition to Timonen, defenseman Andreas Lilja is listed as day-to-day with an upper-body injury. He did not play Monday against Tampa Bay.
Contact Adam Kimelman at email@example.com. Follow him on Twitter: @NHLAdamK
I'm very excited about what happened today. We've worked on this deal with Toronto for a month, or over a month. It got a little bit of legs on draft day, but it really heated up last night, and we were able to complete the deal today.
— Penguins GM Jim Rutherford on Phil Kessel, who he acquired from the Maple Leafs in a trade on Wednesday