The new year started as weirdly as possible for the Heat, but they made it work.

Dwyane Wade suddenly came down with an illness shortly before tipoff and gutted it out for a rare bench appearance. The defense swung erratically from formidable to flimsy. Hassan Whiteside was dropping mid-range jumpers. And, Miami smoothed out all its improvisation for its most lopsided win of the year, clubbing the Mavericks 106-82 Friday at AmericanAirlines Arena.

Whiteside and Goran Dragic did most of the fixing with brilliant performances, and the Heat controlled the action most of the night.

Whiteside matched his career-high with 25 points and made 12 of 16 shots to get there. He also grabbed a season-best 19 rebounds, the most by anyone on the Heat this year. He became the first Miami player to record multiple 25-point, 15-rebound games in the same season since Shaquille O’Neal in 2004-05.

"Hassan was a force," coach Erik Spoelstra said. "He was just so aggressive."

Dragic was not always in sync with Whiteside, but found other avenues to thrive while going for 15 points and seven assists. He scored three times in the paint, including a stunning fastbreak drive to beat Chandler Parsons and J.J. Barea for a layup. Dragic came from the left side, split the defenders, pump faked and flipped it in from the right.

Wade managed to give Miami (19-13) an efficient 19 minutes off the bench with 10 points and seven assists. He made 5 of 6 shots before resting the entire fourth quarter. It was his 10th appearance as a reserve in 812 career games and his second since the 2007-08 season.

The flu-like symptoms came out of nowhere for Wade, who did not mention any illness the past few days and seemed normal in the locker room as he prepared to go through his pre-game routine. The team listed him as a starter on its official lineup card, but he was not on the bench when the game began and Tyler Johnson filled in for him.

Wade felt weak during warm-ups and sat down for a minute to collect himself, then began shaking. He received intravenous fluids in the locker room while watching the first quarter on TV, then felt normal.

"The doc thought I was a little dehydrated, but it was all good," Wade said. "I was fine. I was able to see how they were guarding us, so I came out making plays early. It was easy to come in and play within the flow of the game."

Wade did not check in until midway through the second quarter, and the Heat had things well under control by then with a 14-point lead. After they went up 10 late in the first quarter, they never let Dallas (19-14) get closer than nine points. Miami was up 22 early in the fourth.

The Heat gave up 10 points on 22 percent shooting in the first quarter before allowing 36 on 62 percent in the second. They snapped back by limiting the Mavericks to 16 points in the third quarter and kept them to 36.4 percent for the night.

Dallas, which had won four straight, came in as the No. 8 offensive team in the NBA and had been held under 90 points just twice this season.

Chris Bosh scored 16 points and made 3 of 6 3-pointers to raise his accuracy to 41 percent for the season, by far the best on the team and the best of his career. Gerald Green added 19 points for his 12th double-digit scoring output in 26 games with Miami.

Whiteside, Bosh and others helped slow Dirk Nowitzki to 11 points, and Zaza Pachulia led the Mavericks with 14. Other than Wesley Matthews’ 12, no one else reached double figures for Dallas.

Not only was it big for the Heat to ride out all the rockiness in their roster, but they avoided sinking into a three-game losing streak at a time when they badly need to gain ground. The schedule gets significantly more difficult starting with next week’s West Coast road trip.