Miami - Americans Charley Hoffman and Daniel Berger combined for an eight-under par 64 in Friday's modified alternate shot format to seize a one-stroke lead after two rounds of the 27th annual Franklin Templeton Shootout.
The three-day invitational event hosted by retired Australian star Greg Norman in Naples, Florida, matches 12 pairs of men's golfers in three different styles, Thursday's scramble and Friday's modified alternate shot followed by Saturday's final round better-ball format.
Berger, 22 and the 2015 PGA Rookie of the Year, and Hoffman, 38 and last a winner in 2014 at Mexico, were among nine first-time pairings in this year's event.
They stood on 20-under 124 after 36 holes with two other US duos, Jason Dufner and Brandt Snedeker and first-day leaders Harris English and Matt Kuchar, a stroke adrift.
Dufner and Snedeker matched the leaders for the day's low round.
Americans Billy Horschel and Hunter Mahan were fourth on 127, two shots in front of Northern Ireland's Graeme McDowell and American Gary Woodland as well as American Cameron Tringale and Colombian Camilo Villegas.