Miami ? Eager to begin his latest coaching comeback, Pat Riley arrived for work Monday at 8 a.m. and was surprised to find the Miami Heat offices deserted.

“I didn’t realize it was President’s Day,” he said.

Ah, the old tunnel vision is still there, and Riley hopes to use it to lead a second-half surge by the NBA’s defending champions.

He was back on the practice court Monday evening, nearly seven weeks after he stepped down for operations to replace his left hip and repair cartilage in his right knee. Riley led the Heat through a two-hour workout, their first since the All-Star break.

“It was good to have him back,” center Alonzo Mourning said. “It was basically like he hadn’t left at all.”

For some Heat players, a Riley return is familiar. He quit four days before the 2003-04 season, when Miami was coming off a dismal 25-win season, and returned in December 2005 to lead the franchise to its first league title.

He stepped down again Jan. 3 and now acknowledges the decision wasn’t all about his health. At the time, Miami was 13-17.

“I was not responding very well to the situation,” Riley said. “I was very intolerant of just about anything. I don’t think I was doing a credible job at all as a coach. …

“I have a tendency to get very intimidating and mean and bullying, and I don’t want to do that. That’s what drove me out of the game the first time. I’ve got to get back to coaching and communicating and not just yelling and screaming at people.”

Riley returns with his team at .500 and on the rise. With Shaquille O’Neal healthy and Dwyane Wade in top form, the Heat have won seven of their last eight games to reach 26-26, their best record since they were 3-3.

Despite a rash of health issues, including a knee injury that sidelined O’Neal for much of the season’s first half, the Heat trail Southeast Division leader Washington by only four games. They’ll open the second half tonight in Houston.