Team Jonas Blixt and Cameron Smith took a one-shot lead after the four-ball round at the Zurich Classic of New Orleans.
With this year's Zurich Classic adopting a team-play format for the first time, Friday's second round was four-ball (best ball) after the tournament opened with foursomes.
For four-ball, each team member plays their own ball throughout the entire round, with the best score on every hole recorded.
Swede Blixt and Australian team-mate Smith starred in the format, carding a 10-under-par 62 to be 15 under through 36 holes at TPC Louisiana.
Blixt had an eagle and three birdies, and Smith managed the same at the PGA Tour tournament.
Patrick Reed and Patrick Cantlay (62) are a stroke adrift heading into Saturday's foursomes.
K.J. Choi/Charlie Wi (64) and Troy Merritt/Robert Streb (62) are a shot further back.
Former world number one Jordan Spieth and Ryan Palmer made a late run to stay in the hunt at 12 under.
After sharing the first-round lead in alternate shot, the pairing struggled but a run of three consecutive birdies saw them to another 66.
Brian Stuard/Chris Stroud (64), Alex Cejka/Soren Kjeldsen (62), Charley Hoffman/Nick Watney (65), Xander Schauffele/Tag Ridings (64) and Kyle Stanley/Ryan Ruffels are three shots behind the leading duo.
Jason Day and Rickie Fowler, meanwhile, missed the cut after finishing five under, two strokes adrift of the line following a second-round 68.