American Football: Montana magic holds the key: Super Bowl XXVIII could mean a fairy-tale finale to season between the Chiefs and 49ers. Matt Tench reports

FOR most non-partisans, tomorrow's NFL championship games come down to a simple equation. A case of what the heart would like and what the head expects.

At 37 Joe Montana has collared the sentimental vote, and he will take a lot more than just the hopes of the Kansas City Chiefs with him into Buffalo's Rich Stadium where the AFC Championship and a place in Super Bowl XXVIII are on the line. Should the Chiefs win, a modern sporting fairy-tale would be completed if the San Francisco 49ers, the team with whom Montana won four Super Bowls, were his opponents in this year's big game.

To get there the 49ers must beat the Cowboys, the reigning champions, in Dallas. Like the Chiefs, they must be rated as underdogs.

Montana's second-half performance last weekend in Houston demonstrated that when it comes to game-winning his gifts remain unique. Ten points adrift at the break, and in the face of a frenzied buffeting, Montana rallied his troops with three TD passes and 28 second- half points, 21 of them in the final quarter. 'We can't let Joe Montana beat us,' Darryl Talley, the Bills linebacker, said this week. 'We're playing against the best ever, a great quarterback and competitor.'

The Bills, like Houston, can be expected to harry Montana all game and in defensive end Bruce Smith and outside linebacker Cornelius Bennett have two of the most destructive players in the league.

Montana and the Chiefs did beat the Bills in the regular season, but that match was in Kansas and in the play-offs home advantage is usually decisive. Add to that Buffalo's much greater experience of championship games - they have won the last three AFC titles and are going for their fourth consecutive Super Bowl - and Montana would appear to be battling insurmountable odds. Which is the way he likes it.

Until last weekend's games the Cowboys were rated as the class of the NFC, indeed the NFL. They ended the regular season with a titanic victory in New York, while the 49ers lost three out of the final four games. Then the 49ers, stung by media criticism during a fortnight off, crushed the Giants, while the Cowboys made heavy weather of beating the Green Bay Packers.

In the Cowboy camp they were clearly worried. 'The way we played today there is no possible way we could have beat San Francisco,' Emmitt Smith, their brilliant running back, said. Smith dislocated a shoulder in that victory at the Giants and was re-injured against the Packers.

A crucial part of their offense, the Cowboys insist he will play against the 49ers. 'Emmitt will play and he won't have shoulder problems,' Jimmy Johnson, the Cowboys head coach, ordained. 'I have pronounced him healthy.'

Assuming he is, the Cowboys should prevail and will probably go on to meet the Bills in a repeat of last year's Super Bowl.