Updated

Michigan State's Mark Dantonio was in the hospital again Saturday because of a blood clot in his leg, leaving the 24th-ranked Spartans to play without him for a second straight week.

Dantonio was planning to coach against No. 11 Wisconsin from a box above the field — his first game back following a mild heart attack Sept. 19. But the school announced hours before Michigan State's 34-24 victory that he had been admitted to Sparrow Hospital on Thursday after a routine postoperative exam revealed the clot, which is common after a variety of surgical procedures.

"Coach Dantonio is doing well and his prognosis is excellent," Michigan State athletic director Mark Hollis said. "He was admitted to Sparrow Hospital for monitoring and treatment. The cardiologist told Coach D that it was in his best interest to sit out another game and to stay off his feet."

The school said Saturday his release date from the hospital hadn't been determined and he would watch the game on television — and he may not have been content with merely watching.

"I have never been on the phone so much during a game," defensive coordinator Pat Narduzzi quipped. "He was with us the entire time."

Dantonio's heart attack came shortly after he led his team to an overtime victory over Notre Dame two weekends ago. He was released from the hospital a couple days later but skipped a win over Northern Colorado while offensive coordinator Don Treadwell took over his coaching duties.

Dantonio showed up at his Tuesday news conference this week and said he was going to ease back into his job. He was at practice later that day, and the plan was for him to be in a box against the Badgers.

"We really didn't expect to see him a whole lot," linebacker Greg Jones said. "We went about our business."

Although Dantonio's return was postponed, cardiologist Chris D'Haem said his condition was not particularly unusual.

"Blood clots are not uncommon following a number of surgical procedures and can occur after a cardiac catheterization procedure," D'Haem said. "The clot can block blood flow and cause swelling and pain."

D'Haem performed the initial procedure after Dantonio's heart attack, to put a stent in a blocked blood vessel leading to the heart.

"He was able to attend meetings and practices earlier this week, and since his hospitalization, he has been in regular contact with his coaching staff as well as the team captains and other team leaders," Hollis said.

Michigan State plays in-state rival Michigan, which is also unbeaten, next.