Chi Chi Rodriguez pushed his earnings to $760,679 in the 21 months since he turned 50 by winning the $37,500 first-place check yesterday in the Digital Seniors PGA Classic in Concord, Mass.

The 51-year-old Puerto Rican started the final round at Nashawtuc Country Club with a four-stroke lead over Harold Henning, but by the time Rodriguez putted out at the tournament's 54th hole, his closest pursuer was eight shots behind.

Rodriguez successfully defended his Digital title with a record 18-under-par score on rounds of 65, 66 and 67 for a 198 total and the biggest victory margin of the season on the Senior PGA Tour.

Orville Moody edged past Henning with a 70 for a 206 and $22,500. Henning shot 73 for 208 and third place money of $18,750.

Rodriguez's victory was his sixth this year and the ninth since joining the 50-and-older tour in October. He had eight tournament victories and just over $1 million in earnings during 25 years on the regular PGA Tour.

LPGA: In High Point, N.C., Mary Beth Zimmerman fought off the heat and two challengers on the last five holes for a three-shot victory in the $300,000 LPGA Henredon Classic.

Zimmerman, whose two career victories came in consecutive tournaments in February 1986, had a 6-under-par 66 for a three-day total of 10-under-par 206. The tournament was shortened to 54 holes after heavy rain flooded the Willow Creek Golf Course on Friday.

"I went out and felt I had to shoot anything from a 66 to a 68," Zimmerman said. "I went out and told my caddie we're going to start out right away and fire it right at the pin."

Zimmerman stuck to her word and birdied her opening hole as well as the fourth hole on her way to the $45,000 first prize. Nancy Lopez, Beth Daniel and Laurie Rinker were next at 209.