ESPN NFL

SAN FRANCISCO -- With all the pressure off, the San Francisco 49ers decided to just have fun. Fired-up, fill-in coach Jim Tomsula had a lot to do with that.

The Niners wound up with the kind of performance in their season finale they expected all year. Instead of the playoffs, San Francisco enters an offseason of change. The franchise will soon hire a new general manager, and a coach, then search for a quarterback.

Alex Smith threw a 59-yard touchdown pass to Vernon Davis in what likely was the quarterback's final hurrah with the 49ers, and San Francisco beat Arizona 38-7 on Sunday in a matchup for last place in the awful NFC West.

"We could let our hair down," receiver Ted Ginn Jr. said. "Everybody played comfortably."

Smith, the 2005 No. 1 overall draft pick who becomes a free agent, passed for 276 yards and two TDs and the Niners (6-10) made Tomsula a winner in what will probably be his only game coaching the team. Tomsula was promoted from his defensive line duties after Mike Singletary was fired following a loss last week that eliminated the team from playoff contention for the eighth straight year.

Larry Fitzgerald had a 10-yard TD reception from John Skelton among his 11 catches for Arizona (5-11), which failed to win back-to-back games all year.

Brian Westbrook had a pair of 6-yard TD runs in the third quarter for San Francisco.

The game affected both teams' top-10 picks in April's draft -- exact positioning still to be determined.

These teams went 1-2 in the division a year ago and had high hopes entering 2010, with the 49ers favored to win the West. Instead, they began 0-5 and couldn't produce the franchise's first winning season since its last trip to the postseason in 2002.

"Those guys compete and they play hard no matter what the situation is," Fitzgerald said. "They had a tough week losing their head coach and those guys still were a resilient bunch of guys. We just have to find a way to beat these guys. They swept us the last two years and that doesn't sit well."

Davis finished the year with seven TD receptions, six fewer than a year ago when he tied Antonio Gates' record by a tight end with 13. Tarell Brown added a late 62-yard interception return for a touchdown in San Francisco's second-highest scoring output of the season.

Westbrook, clobbered on an around-the-neck tackle by safety Adrian Wilson late in the first half, had his second big game of the year against the Cardinals. He ran for 136 yards and a score in a 27-6 Monday night victory on Nov. 29 after Frank Gore went down with a season-ending fractured right hip. On Sunday, Westbrook became the only active player and one of four overall with 40 career touchdowns rushing and 30 TDs receiving.

Smith hit Ginn on a 37-yard touchdown pass to the right corner of the end zone to put San Francisco ahead 7-0 late in the first quarter.

Smith was sacked six times in his previous start, a 34-7 loss at San Diego on Dec. 16. Singletary turned back to Troy Smith in last Sunday's loss at St. Louis, then Tomsula made Alex Smith his starter for the season finale.

Alex Smith completed his first six passes before throwing an incompletion late in the first quarter to tackle Adam Snyder, who reported eligible.

"I'm moving forward -- who knows where," said Smith. "No question you want to finish on a good note."

The Niners were 1-for-7 on third downs in the first half and Smith was sacked twice. But San Francisco put together a solid second half for a commanding victory -- though not many fans stuck around to see it. It was a dismal crowd at Candlestick Park on a cool, overcast afternoon after heavy rain fell over night.

The 49ers won their fourth straight in the series. Arizona managed only eight first downs in the last meeting, getting 11 rushes for 13 yards.

Tomsula, determined to send San Francisco into the offseason on a positive note, was all smiles and animated on the sideline. He hugged and high-fived his players throughout the game while also showing off an array of celebratory hand signals. In the final minute, players dumped the cooler on him. Tomsula kissed defensive tackle Isaac Sopoaga on the cheek.

"They just played their hearts out, and they finished," Tomsula said. "One football game is like an entire life: the ups, the downs, the turns, the curves. The team has to do it together and stay together."

San Francisco will surely make a run at Stanford coach Jim Harbaugh after his team plays in the Orange Bowl on Monday night.

The Niners' defense missed four-time Pro Bowl inside linebacker Patrick Willis, who didn't start for the first time in his career. Willis underwent a second surgery on his broken right hand early last week.

Game notes

Second-year 49ers WR Michael Crabtree had four receptions and topped the 100-catch mark for his career. ... San Francisco has gone 22 straight games without allowing a 100-yard rusher, the longest active streak in the NFL. This is the first time since 1997 and the fifth in franchise history the team didn't allow a 100-yard rusher the entire season. ... 49ers LB Ahmad Brooks got his first career interception.