Pro Football Roundup

The Detroit Lions and the Buffalo Bills, two of pro football's laughing stocks in the 1970s, are getting the last laugh in 1980, joining the San Diego Chargers as the only undefeated teams after impressive victories Sunday, the fourth week of the National Football League season.

The Lions, resurgent with rookie running back Billy Sims, healthy quarterback Gary Danielson and an opportunistic defense, crushed the Minnesota Vikings, 27-7. The Bills, paced by quarterback Joe Ferguson and a rugged defense, dominated the Oakland Raiders, 24-7.

San Diego, champions in the AFC West last year, rolled over the winless Kansas City Chiefs, 24-7, but two other teams dropped from the unbeaten ranks. The Philadelphia Eagles couldn't handle Ottis Anderson and fell to the St. Louis Cardinals, 24-14. The Atlanta Falcons knocked the San Francisco 49ers from the unbeatens, 20-17.

Dropping

Besides Kansas City, the New York Jets and New Orleans Saints dropped to 0-4. The Baltimore Colts downed the once highly regarded Jets, 35-21, and the Miami Dolphins scored all their points in the fourth quarter to beat New Orleans, 21-16.

Cakewalk

Elsewhere, the Pittsburgh Steelers rebounded from last week's loss to bury the Chicago Bears, 38-3; the Cleveland Browns outscored the Tampa Bay Bucaneers, 34-27; the Dallas Cowboys whipped the Green Bay Packers, 28-7; the Houston Oilers slipped by the Cincinnati Bengals, 13-10; the Los Angeles Rams routed the New Jersey Giants, 28-7; and the Seattle Seahawks blanked the Washington Redskins, 14-0. Compiled from Wire Dispatches