It was just the fourth win in 23 outings against top 50 opponents for Barrere, who notched the only service break of the match in the eighth game of the deciding set.
On a rainy day when action was moved indoors, American wild-card entry Ben Shelton knocked off No. 7 Sebastian Baez of Argentina 7-6 (1), 6-1. Other first-round winners included Laslo Djere of Serbia, France's Quentin Halys, Jiri Lehecka of the Czech Republic and Americans Marcos Giron and Christopher Eubanks.
Adelaide International 2
No. 8 Tommy Paul defeated Australian lucky loser Christopher O'Connell 6-4, 7-5 in an opening-round match in Australia.
The American saved the lone break point he faced and won 82 percent (32 of 39) of his first-service points. Up next for Paul is Britain's Jack Draper.
Australians John Millman and Jason Kubler also advanced to the second round. Other winners Tuesday included Robin Haase of the Netherlands, Marc-Andrea Huesler of Switzerland, Soonwoo Kwon of South Korea and Mikael Ymer of Sweden.
