Salinda and Velo shot a 14-under-par 58 to take the first-round lead at TPC Louisiana in Avondale, Louisiana.
Playing the best-ball format, Salinda and Velo were a white-hot 12 under through their first 11 holes - via an eagle by Salinda at the par-5 seventh and the rest birdies - before slowing down.
The unheralded team finished with four pars and a birdie over the final five holes.
Salinda is No.163 in the world and Velo No.363, with both yet to win on the PGA Tour.
The scoring record only handed Salinda and Velo a one-shot lead over Danish twins Nicolai and Rasmus Hojgaard, who turned in a 13-under 59. Neither brother made a single bogey.
American pre-tournament favourites Collin Morikawa and Kurt Kitayama are tied for third at 11-under 61 with Davis and Canadian Adam Svensson, plus Paul Peterson and Germany's Thomas Rosenmueller; and Norwegian Kris Ventura and Frenchman Antoine Rozner.
Davis had missed five straight cuts before finishing tied for 13th at last week's $US20 million RBC Heritage in California.
Popular defending champions Rory McIlroy and Shane Lowry opened with an eight-under 64 in McIlroy's first tournament since winning the Masters and completing the career grand slam.
The tournament will turn to foursomes (alternate shot) on Friday. Following the 36-hole cut, it will be four-ball on Saturday and foursomes on Sunday.
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