Nolan Ryan set an all-time major league record with the fifth no-hitter of his career, allowing only three walks as he pitched the Houston Astros to a 5-0 victory over the Los Angeles Dodgers today.

A running one-handed catch by right fielder Terry Puhl in the seventh inning of a ball hit by Mike Sciosia stopped the Dodgers' only serious chance for a hit against the right-hander.

Ryan, 34, was tied with the Dodgers' Sandy Koufax for the most no-hitters in a career. While with the California Angels -- whom he left to sign with Houston as a free agent in November, 1979 -- Ryan threw no-hitters in 1973 against Kansas City on May 15 and Detroit on July 15. The next year, he pitched a no-hitter against Minnesota on Sept. 28 and recorded his fourth no-hitter on June 1, 1975, against Baltimore.

Ryan also has thrown seven one-hitters. The major league record is 11, by Bob Feller.

The victory kept the Astros 1 1/2 games ahead of Cincinnati in the race for the National League West second-half title.

A crowd of 32,115 cheered Ryan's every pitch as he approached the historic achievement. He retired the final 19 batters.

In the final inning, Ryan (10-5) struck out pinch hitter Reggie Smith on three pitches for his 11th strikeout of the game. Ken Landreaux grounded out to Denny Walling at first base, then Ryan ended the game by getting Dusty Baker to ground out to Art Howe at third base.

Of Baker, Ryan said, "I was gonna go to 3-0 before I challenged him (threw him a fast ball). The guy I didn't want to face in that situation, pitching out of the stretch, was the next hitter, Garvey. He's hard for me, with that little strike zone. I really wanted to get that curve over."

He did and Baker hit his routine two-hopper to Howe, who picked it up cleanly. Howe had time to spare, but he turned loose of the ball as soon as he got it, a feathery toss across the diamond. "As soon as I let it go, I knew it was right on the money," Howe said, "so I just followed it across the diamond."

After the final out, Ryan was hoisted onto the shoulders of his teammates and carried off the field as the crowd stood in wild applause. Ryan's wife Ruth rushed onto the field and gave her husband a hug and a kiss.

"It's hard to believe I got the no-hitter," said Ryan "It's the one thing I wanted. I've had a shot at it for a long time. At my age, I thought I wouldn't get it. I don't have the stamina I used to have. I didn't challenge guys in the later innings.

"I really didn't feel like I had good velocity today, but I got ahead on my curve balls . . . The key was my curve ball. You can't win with one pitch. It doesn't matter how fast you can throw, but . . . they had to think about the breaking ball."

The Dodgers did not threaten Ryan with any hard-hit balls in the early going. Scioscia's deep drive to right-center in the seventh was the tester, being caught on the run by Puhl just steps off the warning track.

Ryan's biggest problem was his own control in the second and third innings. Steve Garvey drew a leadoff walk in the second and stole second base. Ryan struck out Pedro Guerrero and Scioscia, but threw a wild pitch to move Garvey to third. Ryan got Ron Roenicke on a pop foul to Howe to end the threat.

In the third, Derrel Thomas led off with a walk and again Ryan came up with two strikeouts, fanning Ted Power and Davey Lopes. Landreaux walked, but Ryan got Baker on a grounder to second.

In the sixth, Ryan, who leads the National League with a 1.74 earned-run average, recorded his 135th career game in which he struck out 10 or more batters by setting down Baker on three pitches.

It was the first no-hitter for a Houston pitcher since Ken Forsch threw one against Atlanta on April 7, 1979.

The last time the Dodgers were no-hit was Aug. 9, 1976 by John Candelaria of Pittsburgh.

It was the third no-hitter in the majors this season. Len Barker of Cleveland threw a perfect game against Toronto, 3-0, on May 15, and Charlie Lea of Montreal no-hit San Francisco, 4-0, on May 27.

The Astros got two runs on three hits off Power (1-3) in the third. Phil Garner led off the inning with a single but was caught stealing. Tony Scott reached base on Thomas' error and Jose Cruz doubled to right, with both Scott and Cruz scoring on Alan Ashby's sharp single to right-center.

In the eighth, Walling walked, went to second on a wild pitch by reliever Dave Stewart and scored on Craig Reynolds' double to make it 3-0.

Ryan bunted Reynolds to third and, after Puhl was intentionally walked, Garner singled to left to score Reynolds and chase Stewart, who was replaced by Steve Howe. Garner scored on Cruz's third hit of the game, a single to right to make it 5-0.

Although he has pitched well this season, Ryan was somewhat of a disappointment to the Astros after signing a four-year, $4 million contract. He was winless from June 19 through Aug. 4, 1980, but was instrumental in the Astros' pennant drive, posting a 4-0 record and 2.45 ERA in August.