DAVIE, Fla. — Ricky Williams is having his best season since retiring.

That was in 2004, when a marijuana habit drove Williams out of the NFL. The following year he began a comeback that proceeded fitfully because of Miami Dolphins coaching changes, a season-ending injury and an 18-month suspension.

The Dolphins stuck with Williams, and now he might just save their season. Picking up the slack for injured starter Ronnie Brown, the 32-year-old Williams totaled 221 yards rushing in two games over a five-day stretch, and Miami (5-5) won both to reach .500 for the first time this year.

“It puts us on the right track,” Williams said. “We have been trying to get here all year, and we finally got here. It’s just the next step to where we want to go.”

Williams is leading the way. Making his first start of the year in Thursday’s 24-17 victory at Carolina, he rushed for 119 yards and two scores and added a 14-yard touchdown catch. It was his second three-TD game this season, and the first time in his career he scored rushing and receiving in the same game.

“I was really impressed with Ricky,” coach Tony Sparano said Friday. “He did a tremendous job. He ran the ball hard, really hard.”

Williams scored once as Brown’s replacement taking the snap in the wildcat. He scored on a 46-yard dash to seal the win, outrunning the Panthers’ secondary to the end zone. He carried 22 times — not a lot for a back who once had 392 attempts in a season, but his highest total in four years.

The 100-yard game was Williams’ 22nd with Miami, extending his franchise record. He’s the oldest 100-yard rusher in team history.

“He’s not 32, I don’t care what he says,” rookie receiver Brian Hartline said. “He definitely doesn’t look 32 out there, and he definitely has a lot of gas left in his wheels.”

Williams never fit the mold of the typical NFL player, and that’s still the case. Last spring he agreed to a contract extension for 2010 without an agent or negotiations. Working toward a college degree, he wants to become an osteopath. He’s so particular about his diet that Sparano laughingly speaks of “Ricky food.”

And Williams remains skittish with the media.

“I don’t like talking about myself,” he said after Thursday’s game.

Instead, teammates gushed about him. Younger players seemed especially tickled to see him trample Panthers.

“He has been here for a long time, and he knows what he’s doing,” receiver Ted Ginn Jr. said. “When he sees something, he was just trying to run through. That was what he was taught to do as a young ’un.”

Sparano said he’s confident Williams can handle a starter’s workload the rest of the season, and the Dolphins really have no choice but to rely heavily on their only thirtysomething offensive player.

Brown underwent season-ending surgery Friday on his broken right foot. Williams’ backup, second-year pro Lex Hilliard, had his first career rushing attempt Thursday night. And the passing attack ranks third-worst in the league.

That means Williams, seven years removed from his NFL rushing title, will try to carry Miami to the playoffs.

“It’s hard to replace Ronnie Brown,” Hartline said. “But Ricky Williams is still Ricky Williams.”

Even with limited playing time this season, Williams is on pace for his first 1,000-yard season since 2003. He’s averaging a career-best 5.3 yards per carry. And he ranks among NFL leaders with 10 touchdowns.

At Charlotte, Williams thrived behind a patchwork front. Four Miami offensive linemen left the game with injuries, and the Dolphins used three centers, including one moved from tackle who had not practiced snaps.

“It’s tough,” Williams said. “Guys are dropping like flies.”

“We were down to me going in the game,” said Sparano, a former center. “I’ve never seen anything like it.”

Sparano provided no update Friday on the severity of the injuries. Players have the weekend off before beginning preparations to play the Buffalo Bills on Nov. 29.

“We’ll get a chance to heal up,” Sparano said. “Right now the boys need a bit of rest.”

Even Williams “got a little bit dinged” in the fourth quarter but was expected to be fine, Sparano said. The most serious injury appeared to be to nose tackle Jason Ferguson, who hurt his right knee and underwent an MRI.

Despite the heavy toll, Sparano was in a cheerful mood Friday. After winning three games in the first 63 days of the season, the Dolphins won twice in five days, and they’re only one victory behind AFC East leader New England.

“There’s a lot of football left,” Sparano said.

Look for lots of handoffs to Williams in the weeks to come. Over the years the Dolphins are 19-3 when he rushes for 100 yards.

“Hopefully he can rest up these next 10 days,” teammate Jason Taylor said, “and do it again next week.”