An echo of Tarkenton from BYU

From the rim of the press box in San Diego stadium, site of this year's Holiday Bowl, quarterback Jim McMahon of Brigham Young University looked like an updated version of Fran Tarkenton, who took his act to the National Football League and made it last for 18 years.

Also like Tarkenton, Jim seems considerably shorter than 6 feet, although this is how BYU lists him in its media guide. Anyway, he was voted the game's Most Valuable Player as his team defeated Washington State, 38-36, for its 11th victory of the season.

Outstanding performances are the norm for McMahon, and in this game, often on what appeared to be broken plays, he completed 27 of 43 passes for 324 yards and three touchdowns. Several pro scouts got it all down in their notebooks, including how well Jim can scramble.

McMahon, a senior who holds 57 NCAA offensive records, is going to go high in this year's NFL college player draft - probably not first, but high. Still, there is always that flicker of doubt in general managers' minds about a kid who stands less that 6-3 and would have to put weights in his pockets to reach 200 pounds.

What making the pros for a quarterback generally comes down to, providing he is big enough and strong enough, are the velocity in his throwing arm and how quickly he releases the football. If he consistently needs more than three seconds to find his receivers, the world is probably about to get itself another used-car salesman.

Asking Brigham Young's Head Coach LaVell Edwards if he thinks McMahon can make it big in the pros is logical, but hardly conclusive. I haven't met a college coach yet who can weigh the relative merits of his own quarterback without at some point resting his thumb on the scales. Maybe they don't always mean to, but they do.

Said Edwards: ''If I were the general manager of a pro team that needed a quarterback and had the first shot in this year's draft, I'd make Jimmy No. 1 pick. This kid has got it all. He won't have to change a thing about the way he plays quarterback to make it in the National Football League. It's not hard at all for me to see him someday taking an NFL team to the Super Bowl.''

Washington State Coach Jim Walden, whose defense never really contained McMahon when it counted, was also asked to comment on Jim.

''Basically, McMahon is the best get-into-a-mess-and-then-get- something-good-out-of-it quarterback in the nation,'' Walden said, ''and he makes this happen too often for it to be luck. We knew from the films we'd seen of Jim and from our scouting reports that we were going to have trouble stopping him. But we didn't quite realize just how good a scrambler he is.''

The main problem McMahon will probably face as an NFL player, besides a lack of height that never seemed to bother Tarkenton, for example, are the 101 pass coverages that he will see in the pros.

Just to give you an idea of how closely pass receivers are watched in the NFL , there is single coverage; zone coverage; double coverage; combination coverage; and weak side zones. That kind of thing is not learned overnight, no matter how many opponents' films you watch. And this is one area where Jim reportedly has not worked as hard as he should have.

McMahon, who has the confidence of a marine from Texas, says if he weren't bound by NFL draft rules, he'd most like to play for the San Francisco 49ers, since he grew up only 40 miles from Candlestick Park. His second choice would be the Los Angeles Rams.

''But to be realistic about it, I'm probably going to wind up with a down team that wants to change quarterbacks,'' Jim explained. ''I can accept that, and I think my chances of playing in a situation like that are certainly greater than with a franchise like San Francisco.

''Even though I'll be learning a new system in the pros and my receivers will be different, that's what practices are for,'' he continued. ''I know I throw a ball people can catch, and if there is a broken play I can scramble out of it.''

With the kind of statistics McMahon had in 1981 during the regular season, most pro scouts like his chances. For the record, he completed 64 percent of his passes for 3,555 yards and 30 TDs. With Jim at the controls, BYU this year lost only two of 13 games.