Xander Schauffele left first-round leaders Rory McIlroy and Tiger Woods trailing in his wake with a second-round 64 at the BMW Championship.
Schauffele is in need of a strong performance at Aronimink Golf Club as this marks the final week before Jim Furyk reveals the last of his four United States Ryder Cup wildcard picks.
The American narrowly missed out on earning an automatic spot in the team and then earlier this week saw Woods, Phil Mickelson and Bryson DeChambeau receive picks ahead of him.
There is also strong rumour that in-form Tony Finau will take the final pick, but much will depend on Schauffele's showing this weekend.
EXCLUSIVE: XANDER SCHAUFFELE TALKS TO GOLFMAGIC
Schauffele has opened up a two-stroke lead over Justin Rose on 13-under par after 36 holes.
Keegan Bradley, Alex Noren, Hideki Matsuyama and Rickie Fowler are three strokes back on 10-under par, with McIlroy on 9-under alongside defending FedEx Cup champion Justin Thomas.
Woods could not match the same form as his blistering first-round 62 and ended up bogeying the final two holes for a disappointing round of 70 to remain on 8-under.
The top 30 in the FedEx Cup after this week will then head to the season-ending Tour Championship in two weeks time, a week before the Ryder Cup.