A roundup of the week May 12-18

PRO BASKETBALL—With a 123-107 victory, Los Angeles won its NBA championship series with Philadelphia four games to two (page 18).

BOXING—SHOJI OGUMA of Japan knocked out defending champion Park Chan-hee in the ninth round in Seoul to win the WBC flyweight title.

GOLF—BRUCE LIETZKE shot a nine-under-par 271 to win the $300,000 Colonial National Invitational in Fort Worth by one stroke over Ben Crenshaw.

Donna Horton White defeated Debbie Massey on the first hole of sudden death to win a $125,000 LPGA tournament in Clifton, N.J. They ended regulation play at two-under-par 217.

HARNESS RACING—NIATROSS ($2.40), Clint Galbraith in the sulky, won his first start of the season, the $55,000 Hanover Hempt Stakes at Vernon Downs, by 3½ lengths over Majestic Lobell. The 3-year-old colt, who is unbeaten in his 14 races, covered the mile in 1:56[1/5].

HOCKEY—With a 6-2 home-ice victory, the Islanders moved ahead of Philadelphia two games to one in the Stanley Cup championship series (page 74).

HORSE RACING—CODEX ($7.40), ridden by Angel Cordero Jr., defeated Genuine Risk by 4¾ lengths to win the $250,600 Preakness at Pimlico. The 3-year-old was timed at 1:54[1/5] for the 1[3/16] miles (page 26).

Spectacular Bid ($2.40), Bill Shoemaker up, defeated Peregrinator by seven lengths to win the $210,400 Mervyn LeRoy Handicap at Hollywood Park. The 4-year-old ran the 1[1/16] miles in 1:40[2/5].

Weber City Miss ($6.80), Vince Bracciale up, defeated Bishop's Ring by 2¼ lengths to win the $114,800 Black-Eyed Susan Stakes for 3-year-old fillies at Pimlico. She covered the 1[1/16] miles in 1:44[2/5].

MOTOR SPORTS—CARLOS REUTEMANN, averaging 81.20 mph in a Williams, won the 38th Grand Prix of Monaco. He finished 1:13.63 ahead of Jacques Laffite, who drove a Ligier.

Bobby Allison, driving a Thunderbird at an average speed of 113.866 mph, won the 12th Mason-Dixon 500 at the one-mile Dover (Del.) Downs International Speedway. He finished 26 seconds ahead of Richard Petty, who was driving a Monte Carlo.

SOCCER—NASL: On the strength of the goaltending of Jack Brand, Seattle (9-1) stayed atop the National Conference Western Division with the league's best record (page 86). New York, leading the National Conference East at 7-2, triumphed 4-1 at California as Giorgio Chinaglia had his 102nd and 103rd NASL goals to become the league's alltime leading goal scorer. With a 2-1 victory over New England—Midfielder Billy Gazonas hit the game-winner in a shootout—Tulsa (6-2) took over first place in the National Central from Dallas, which lost 1-0 to Los Angeles as Midfielder Leo Van Veen had the only goal. Fort Lauderdale, atop the American Conference East with an 8-2 record, won 2-1 against Washington on goals by Gerd Mueller and Eduardo Bonvallet, while second-place Tampa Bay (6-3) defeated Vancouver 3-2 on Sunday as Oscar Fabbiani hit the game winner with 17:57 remaining. Chicago (7-1), pacing the American Conference Central, got its fourth consecutive home triumph, a 3-2 win over Detroit, as Forward Tasso Koutsoukos scored twice. San Jose, in last place in the American West, one week ago picked up Forward Steve David from San Diego, and David, a seven-year veteran, quickly helped the Earthquakes to their first two victories. He scored the only goal in San Jose's 1-0 triumph over Edmonton and all three in its 3-0 victory over Houston. Those four goals brought David's NASL point total to 200, a plateau reached by only four other players.

ASL: Golden Gate had a long week away from home, playing to a double-overtime 2-2 tie at Miami and losing 3-2 at Columbus. The Magic (5-2-1) was still leading the National Conference, while Sacramento (also 5-2-1) held its lead in the American with a 1-0 victory over California. In that game Midfielder Greg McKeown scored the only goal.

TENNIS—JOHN McENROE defeated Victor Amaya 6-2, 6-3 to win the men's title in a $175,000 tournament in Kobe, Japan. MARTINA NAVRATILOVA beat Pam Shriver 7-5, 6-3 for the women's crown.

Harold Solomon defeated Guillermo Vilas 6-7, 6-2, 6-4, 2-6, 6-3 to win a $200,000 tournament in Hamburg, West Germany.

Jimmy Connors defeated Eddie Dibbs 6-2, 6-3 to win the $104,000 Louisville (Ky.) International Classic.

TRACK & FIELD—DALEY THOMPSON of Great Britain established a world record in the decathlon by scoring 8,622 points in Goetzis, Austria. Thompson surpassed the mark of 8,617 set by Bruce Jenner of the U.S. in the 1976 Olympics.

Karin Rossley of East Germany set a women's world record of 54.28 in the 400-meter hurdles in Jena, E. Germany. She surpassed by half a second the mark established last year by Marina Makeyeva of the U.S.S.R.

Yuri Sedykh established a world record of 264'7" in the hammer throw at a Soviet meet in Leselidze. His throw surpassed the 1978 record of Karl-Hans Riehm by one foot, one inch.

WEIGHTLIFTING—SERGEI POLTORATSKY of the U.S.S.R. established a world record in the 220-pound weight class by jerking 501.5 pounds at the Soviet championships in Moscow. He surpassed by 3½ pounds the mark set by compatriot David Rigert. In the same competition, VIKTOR NANIYEV snatched 401 pounds, two pounds more than the world record set by Rigert at the recent European championships in Belgrade.

MILEPOSTS—CONVICTED: By a Federal district court jury in Detroit, ANTHONY TASSONE, 53, a reputed underworld figure from Trenton, N.J., on one count of conspiracy to fix horse races and five counts involving fixed races at Detroit Race Course and Hazel Park raceway. The jury also convicted former Jockey BENJAMIN SERIDO, 45, of Mount Carmel, Ohio, on one charge of conspiracy and one count of wire fraud. The case against Detroit trainer Michael Marion, 49, resulted in a hung jury, as did four of the counts against jockey Larry Kunitake, 40, also of Detroit. Kunitake was acquitted of a wire fraud charge.

HIRED: As basketball coach at San Francisco, PETE BARRY, 32, to replace Dan Belluomini, under whom he had been an assistant for two seasons.

TRADED: By the Dallas Cowboys, Linebacker TOM (Hollywood) HENDERSON, 27, to the San Francisco 49ers for an undisclosed draft choice in 1981.