Fastest in GT Le Mans practice at Michelin Raceway Road Altanta was Vanthoor, who headed up a one-two for the CORE autosport-run Porsche North America squad, sportscar365.com reports.

Vanthoor led a Porsche sweep of the top two positions in opening practice for this weekend's Michelin GT Challenge at Virginia International Raceway. The defending IMSA GT Le Mans class champion reeled off a 1:41.550 lap to go quickest in the 60-minute scheduled session, sportscar365.com reports.

Vanthoor emerged as the pole-sitter in GT Le Mans Saturday at Road America following a highly competitive battle for top honors in the session, sportscar365.com reports.

Vanthoor was fastest in Friday's GT Le Mans practice for the Cadillac Grand Prix of Sebring at Sebring Raceway. He turned a fast lap of 1.59.501.

In GT Le Mans opening practice for the Rolex 24, Porsche led the way, which ran first and second with its new 2019-spec Porsche 911 RSR. Vanthoor set the pace with a time of 1:57.031 while Nick Tandy backed up his teammate with a 1:57.351, sportscar365.com reports.