Kelly Is Ready to Play : AFC playoffs: Buffalo quarterback expected to face Dolphins today.

Jim Kelly, the NFL’s top-rated passer, appears to be ready to play after a month of rehabilitating his knee. But who would bet against Dan Marino in the clutch?

Thurman Thomas rushed for 154 yards against Miami in Buffalo’s 24-14 AFC East title-clinching victory three weeks ago. But can the Bills’ defense forget that Miami held the ball for more than 39 minutes en route to a 30-7 victory early in the season?

The temperature may not hit 30 degrees today at Rich Stadium in Orchard Park, N.Y., and more than a foot of snow could have fallen overnight. But will that be enough to cool off Marino, who completed nine consecutive passes for 114 yards to climax last Saturday’s first-round victory over the Kansas City Chiefs?

Buffalo (13-3) will be favored over the Dolphins (13-4) for today’s AFC divisional playoff game--and a little snow on a frozen field shouldn’t hurt its chances any--but it wouldn’t be an earth-shaking upset if Marino and the Dolphins prevailed.

Twelve of the last 15 teams to win 13 regular-season games have gone on to the Super Bowl, and the Bills are one of the NFL’s few well-rounded teams, but there are several factors to consider in this colorful rivalry:

--Kelly has been cleared to play, but he’s apparently not feeling all that great. This brings us to Frank Reich, who completed only seven of 14 passes before giving way to third-string quarterback Gale Gilbert in the Bills’ season-ending defeat by Washington. It was the first time in Reich’s five starts that Buffalo has lost, however.

“The season isn’t over yet,” Reich said. “My attitude is to stay ready. Hopefully, Jim will come back and lead us all the way. But I’m sure he will be a little bit more tender than normal, so I want to be prepared.”

--With either Kelly or Reich taking the snaps, the Bills should have a good enough passing attack to keep Miami from putting everybody on the line of scrimmage to try to stop Thomas, who led the NFL for the second consecutive season with 1,829 yards from scrimmage.

The Miami defense ranked No. 1 in the league for much of the year before ending up seventh. The Dolphins are fifth in the league in pass defense--Kansas City picked up enough yardage for a first down on only one of 11 third-down plays--and they were third in the AFC in sacks with 45.

But the Dolphins are ranked only 16th against the rush. And when they last came to Buffalo to play a game that the Dolphin players characterized as their most important in five years, Buffalo’s running attack dominated.

--The big difference in Miami this season has been the semblance of a running attack to complement Marino and Co. Make no mistake, this is no three-yards-and-a-cloud-of-dust outfit, but Sammie Smith, who gained 82 yards in 20 carries last week, is enough of a threat to keep defenses honest.

The Bills’ defense is talented and balanced, however, and seldom has to cheat. Anchored by Bruce Smith, the NFL’s defensive player of the year who had 19 sacks this season, the Bills ranked seventh in the league against the pass.

--The Upstate New York weather may not bother the Dolphins as much as the Upstate New York fans. When they played here Dec. 23--the game that decided whether this game would be played in sunshine or snow, remember--the fans stormed the field, tore up the artificial turf, pulled down the goal posts and broke windows on the Dolphins’ bus after the game.

“If you let them get into it, it can be a heck of a distraction,” Miami’s rookie guard, Keith Sims, said. “They’re loud, they scream, they yell, they try to mock you on the sidelines.”

Dolphin safety Louis Oliver admires the rowdy Bills’ faithful, however, calling them “the greatest fans in the league.” And he adds: “If we win, we’re going to tear down the goal posts.”

The Erie County police will make sure Buffalo revelers do not, however. They’re even importing some more canine support in an effort to put a dog show of force along the sidelines in the closing minutes to dissuade fans from running onto the field.

With this season’s series even at 1-1, today will mark the first time these old American Football League rivals have had three meetings in one season.

“What better way to settle a tiebreaker,” Oliver said, “than in the playoffs?”

AFC Playoff Notes

Miami’s All-Pro linebacker, John Offerdahl, is doubtful because of a sprained left arch, an injury he aggravated in last week’s victory over Kansas City. Offerdahl couldn’t wear a shoe until Thursday and is still limping. If he can’t play, Mike Reichenbach will probably start.

Miami was 9-3 and Buffalo 11-1 against common opponents this season. Both beat Indianapolis, New England and the New York Jets twice, and Cleveland, Philadelphia and Phoenix once; both lost to Washington. Miami lost to the Raiders and New York Giants and Buffalo beat them.