A roundup of the week Sept. 29-Oct. 5

BOXING—LARRY HOLMES retained his WBC heavyweight title in Las Vegas when Muhammad Ali failed to come out for the 11th round (page 34).

Saoul Mamby successfully defended his WBC super-lightweight championship by scoring a unanimous decision over Termite Watkins in Las Vegas.

Eusebio Pedroza won a split decision from Rocky Lockridge to retain his WBA featherweight title in McAfee, N.J.

PRO FOOTBALL—Defenses provided both excitement and points in the fifth week of play as only Buffalo remained unbeaten. An interception by Bills Linebacker Jim Haslett set up the winning touchdown in Buffalo's 26-24 upset of San Diego, which had entered the game with the league's highest-scoring offense and a perfect record. Detroit, which also had been 4-0, lost 43-28 to Atlanta as the Falcons held Billy Sims to 21 yards on 14 carries and returned two fumbles and a blocked punt for TDs. The victory moved Atlanta into a tie for the NFC West lead with L.A. and San Francisco, who met head on in Anaheim, the Rams winning 48-26. Interceptions carried Pittsburgh to a one-game lead over Houston in the AFC Central, as the Steelers picked off five of Tommy Kramer's passes to beat Minnesota 23-17 and Oiler Quarterback Ken Stabler threw an equal number to the Seahawk secondary in a 26-7 loss to Seattle. A 93-yard interception runback by Denver Linebacker Randy Gradishar gave the Broncos their only TD in a 19-16 victory over Cleveland. Fred Steinfort had four field goals for Denver. In a 23-14 loss to New England on Monday night, the Broncos had been held to 170 yards on offense, their lowest total in 30 regular-season games. With newly re-signed Cornerback Mike Haynes returning a blocked field goal try 65 yards for a touchdown, the Pats won again on Sunday, 21-11 over the Jets, to stay a game behind Buffalo in the AFC East. Dallas and Philadelphia still share the NFC East lead following the Cowboys' 24-3 win over the Giants and the Eagles' 24-14 victory over Washington. Elsewhere, several hours after Green Bay's board of directors gave Coach Bart Starr a vote of confidence, the Packers beat Cincinnati 14-9; Bert Jones victimized the injury-weakened Miami secondary for 282 yards passing as Baltimore defeated the Dolphins 30-17 (page 82); previously winless Kansas City beat Oakland 31-17; and still winless New Orleans lost to St. Louis 40-7.

GOLF—JERILYN BRITZ birdied the second playoff hole to defeat Nancy Lopez Melton and win a rain-shortened $150,000 LPGA tournament in Dallas. Britz and Melton finished the 35 holes tied at 139, one under par.

Mike Sullivan won the $200,000 Southern Open in Columbus, Ga. with an 11-under-par 269, finishing five strokes ahead of Johnnie Miller and Dave Eichelberger.

Kathy Whitworth and DONNA CAPONI YOUNG finished at 195,24 under par, to win the $115,000 LPGA team title in Portland by four strokes over Janet Alex and Judy Clark.

HARNESS RACING—NIATROSS, driven by Clint Galbraith, set a world record for a mile paced on a one-mile track (1:49[1/5]) in a time trial at The Red Mile in Lexington, taking nearly three seconds off Steady Star's 1971 mark (1:52).

Final Score ($4.40, $2.80), Tom Haughton driving, won the $100,000 Kentucky Futurity for 3-year-old trotters by taking the second (1:58) and fourth (2:06[2/5]) one-mile heats, in Lexington.

HORSE RACING—Jacinto Vasquez rode FRENCH COLONIAL ($23.40) to a 1½-length victory over Just A Game II in the $140,500 Man o' War Stakes on the turf course at Belmont, covering the 1‚Äö√Ñ√∂‚àö√±‚àö‚à´ miles in 2:15[2/5].

Jaklin Klugman ($2.20), Chris McCarron aboard, won the $107,400 Hawthorne Derby at the newly rebuilt Hawthorne Race Course by 3¼ lengths over Summer Advocate. The 3-year-old colt covered the 1[1/16] miles in 1:40[4/5].

Pat Eddery rode DETROIT ($7.70), a 3-year-old filly, to a half-length victory over Argument in the $490,000 Prix de l'Arc de Triomphe in Paris, finishing the 1½ miles in 2:28.

Temperence Hill ($6.60), Eddie Maple in the irons, won the $549,000 Jockey Club Gold Cup at Belmont by 5½ lengths over John Henry. The 3-year-old colt's time for the mile and a half was 2:30[1/5] (page 99).

MOTOR SPORTS—DALE EARNHARDT, averaging 135.285 mph in a Chevrolet, beat Cale Yarborough, also in a Chevrolet, by 1.83 seconds to win the $320,000 National 500 on the 1.5-mile oval in Harrisburg, N.C.

Alan Jones, in a Williams, won the U.S. Grand Prix in Watkins Glen, N.Y. by 4.2 seconds over Carlos Reutemann, also in a Williams. Jones, the world Formula I driving champion, averaged 126.37 mph over the 3.377-mile circuit (page 86).

ROAD RACING—MATTHEWS MOTSHWARATEU, a South African student at the University of Texas, El Paso, and JAN MERRILL of Waterford, Conn. won national 10-km. titles in Purchase, N.Y., Motshwarateu being timed in 27:59, Merrill in 32:29, a U.S. women's record. The race, the first in a prize-money Grand Prix circuit, awarded $50,000 to the clubs of the top 20 men and top 30 women.

TENNIS—JOSE LUIS CLERC defeated Guillermo Vilas 3-6, 6-1, 6-1, 4-6, 6-2 to win a $125,000 tournament in Madrid.

Eliot Teltscher beat Tim Wilkison 7-6, 6-3 to win a $100,000 tournament in Kaanapali, Hawaii.

Tracy Austin won the $100,000 U.S. Women's Indoor Championship in Bloomington, Minn. by defeating Diane Fromholtz 6-1, 2-6, 6-2.

MILEPOSTS—DECLARED: A free agent by NHL Commissioner John Ziegler, Hartford Right Wing BLAINE STOUGHTON, 27, who tied Danny Gare and Charlie Simmer for the league lead in goals last season with 56. Ziegler ruled that the Whalers had failed to renew Stoughton's contract or offer him a new one by a July 1 deadline.

DROPPED: By the Women's Professional Basketball League, its New York, Iowa, Houston and Milwaukee franchises, leaving the league with nine teams. Sherwin Fischer, 48, one of the owners of the Chicago Hustle, was named interim commissioner, replacing WBL founder Bill Byrne, 44, who resigned.

FIRED: After managing the San Diego Padres to a 73-89 record and a last-place finish in the National League West, JERRY COLEMAN, 56, who will return to his job as a Padres broadcaster.

Texas Rangers Manager PAT CORRALES, 39, whose team finished fourth in the American League West with a 76-85 record. In slightly more than two seasons under Corrales, the Rangers were 158-165.

With five games left in the season, Boston Red Sox Manager DON ZIMMER, 49, who was replaced on an interim basis by Coach Johnny Pesky. In 4½ seasons under Zimmer, the Red Sox were 411-314, but failed to win an American League East title. They were in third place, 16 games out, at the time of his dismissal.

MOVED: To Calgary, Alberta beginning next season, the NASL Memphis Rogues, who were purchased last month by Canadian businessman Nelson Skalbania.

RETIRED: Boston Celtics Center DAVE COWENS, 31, a former NBA Rookie of the Year (1970-71) and MVP (1972-73) who averaged 18.2 points and 14.0 rebounds per game over 10 seasons. A first-round draft pick in 1970, he led the Celtics to two league titles and in 1978-79 had a 27-41 record as player-coach.

RETIRED: SPECTACULAR BID, 4, winner of the 1979 Kentucky Derby and Preakness as well as a record $2,781,607 in purses. Bid was scheduled to run in the Jockey Club Gold Cup on Saturday, but less than two hours before the race Trainer Bud Delp scratched the colt, who was suffering soreness in his left front ankle, and announced the retirement (page 99).