Thunderstorms and a cold wind blew across the TPC-San Antonio course Friday, forcing a delay of 3 hours, 15 minutes. There were 33 players from the 81-man field still on the course when darkness brought a stoppage of play.
Calcavecchia, wearing a heavy sweater to fight off the first blast of winter-like weather in south Texas, birdied five holes on the back nine.
Kenny Perry was alone in second at 3-under when play was stopped. He had three holes yet to play.
Tom Kite, a native Texan who has never won in the state on either the PGA or Champions Tour, shot a 2-under 70. Willie Wood, who was also at 2-under with one hole left.
This is the next-to-last event on the Champions Tour this year and Bernhard Langer has the points lead in a bid to capture a $1 million annuity at the end of the season.
Langer was 2-over with two holes to play, tied for 24th place. Defending champion Fred Couples isn't playing this week after his chronic back problems once more became an issue.
Celebrity Couples of 2014 [PHOTOS]