Senior, 53, lost in a playoff earlier this year to Corey Pavin for one of his eight Top 10 finishes of the season.
He did not make a bogey on a windy day at the Kapolei course and finished the round one shot in front of Bill Glasson and Jay Don Blake.
Among those at 65 was Gary McCord, who at age 64 limits his golfing activity almost exclusively to his job as a broadcaster for CBS-TV. This is only his fourth appearance on the Champions Tour in the last three years.
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