PRO FOOTBALL : Bears, 49ers Play for the Edge Tonight : NFC’s Two Best Teams Meet With Home-Field Advantage at Stake

San Francisco 49ers have a home-field advantage over the Chicago Bears this time around and a healthier quarterback, too, with Joe Montana coming off a record-breaking performance.

Chicago’s Jim McMahon pulled a hamstring muscle last week and is questionable as a performer in tonight’s game between the playoff-bound teams with 10-2 records, best in the NFL. Mike Tomczak will handle the Bears’ passing if McMahon stays on the sidelines.

“There’s not an awful lot of difference, to be honest with you,” San Francisco Coach Bill Walsh said of the two quarterbacks.

Tomczak took over for the injured McMahon late in last Sunday night’s game against Minnesota and threw a 38-yard touchdown pass to Dennis Gentry with 40 seconds to play. The Bears won, 30-24, to clinch the NFC Central title for a fourth consecutive year.

“Now we need to work on (playoff) home-field advantage. We know what we face this week and we know it will take a great team effort to win,” Coach Mike Ditka said.

But he places a high priority on having his No. 1 quarterback at full strength for the playoffs, which could very well include a Bear-49er rematch, perhaps for the conference championship, back in Candlestick Park or at Chicago’s Soldier Field.

McMahon missed postseason play because of injuries in two of the last three years. The one time he was available, two years ago, Chicago won the Super Bowl.

“Our fans would like it if he didn’t show up,” Walsh said.

San Francisco, leading the NFC West, assured itself of at least a wild-card playoff berth with a 23-12 victory over Green Bay last week. Montana completed his first 17 passes of the game, giving him an NFL-record streak of 22 straight completions in a two-game stretch.

Montana’s season passing statistics include a career-high 29 touchdown passes, at least one in every game. Wide receiver Jerry Rice has 15 touchdown receptions, 3 short of an NFL record, and his streak of 10 straight games with scoring catches puts him within one game of another league record.

“I don’t know how we’re going to stop Rice and Montana. No one else has stopped them,” Ditka said.