Sport: Mack the Mini-Knife

If Mack Herron had carried a passport in his younger days, he could have listed his profession as loser. He majored in football at Kansas State, claimed that friction with his coach cost him a nomination for the Heisman Trophy, and quit school minus his degree. Pro offers were paltry, so Herron went to Canada. There he led the Canadian Football League in rushing but failed to awe the Winnipeg police. When they busted him for possession of marijuana, the Winnipeg Blue Bombers fired him. In 1973 he was back home in Chicago selling blue jeans for a living.

It was altogether fitting that when Herron finally got an N.F.L. offer, it came from the feckless New England Patriots. Though Herron led the league in kickoff returns and return yardage last season, the team ran up a discouraging record of 5-9. But this fall Head Coach Chuck Fairbanks put Herron in the starting backfield, made a few other adjustments, and suddenly Boston was the cradle of rebellion against the N.F.L.'s reigning powers. The Pats opened the season by trouncing the champion Dolphins, beat the Giants and for an encore knocked off the powerful Rams. Going into last weekend, the Pats stood tall as the only undefeated team in the league's American Conference.

Standing tallest, at least figuratively, is Herron, the N.F.L.'s shortest player. A mere 5 ft. 5 in. but weighing 170 Ibs., Herron has earned the nickname Mini-Mack from suddenly rabid New England fans, and new respect from befuddled opponents. "I realize it's a big man's game," says Herron. "I use the big linemen as a shield. I stay real low, lower than I really am, so the defense don't know where I'm at."

Undaunted and rarely located by bigger defenders, Herron knifed through the Ram defense for 38 yds. on one punt return that set up a field goal and led the Patriots in rushing yardage from scrimmage with 62. The skittery running back, with legs like fireplugs and a gold stud festooning his left earlobe, leads his team in rushing yardage and touchdowns.

Coach Fairbanks admits that Her-ron's reputation initially gave him pause. Now he credits Mack with "putting a spark in this team." Quarterback Jim Plunkett, who has developed into one of the most effective tacticians in the N.F.L. this season, goes one step further. He calls Herron the team's "catalyst." In fact, Mack is just one of them. Plunkett has combined with College Teammate Randy Vataha for a crucial touchdown pass against the Giants and the game winner against the Rams. And Fairbanks has molded a three-linemen, four-linebackers "sponge" defense that has dampened opponents' rushing games. Going into last weekend's contest with the Baltimore Colts, the sponge had given up only two more yards on the ground than O.J. Simpson alone gained in his record-breaking 250-yd. game against the Patriots last September.