Graeme McDowell and partner Henrik Stenson sit in a tie for sixth place at the Zurich Classic as play was suspended due to darkness.

The Irishman and the Swede hit a second-round 67 in the alternate-shot format to sit two shots off the lead on 12 under par.

Peter Malnati and Billy Hurley III moved to the top of the leaderboard at the weather-affected tournament in Louisiana. 

Catching up after a rain-delayed first-round, the American pair shot a best-ball nine-under 63 in the morning's four-ball format, before carding a second-round 67 in alternate-shot play to move to 14 under overall.

They posted a bogey-free second round and picked up shots at the second, sixth, 11th, 13th and 17th.

Seamus Power, playing alongside Canadian David Hearn, sits in a tie for 20th following two consecutive 68s, while Padraig Harrington and Shane Lowry struggled in their second round, posting 75 and undoing their great work in the first round where they hit 65. The Irish pair will not be around for the weekend as they are four shots off the projected cut.

Scotland's Russell Knox and American Brian Stuard sit in a tie for second just one shot behind having carded a second-round 69.

First-round leaders Brian Gay and Rory Sabbatini also moved to 13 under alongside Scott Stallings and Trey Mullinax, and Kevin Kisner and Scott Brown, in incomplete rounds.

Gay-Sabbatini and Kisner-Brown completed four holes in the second round, after carding 60 and 62 respectively in the first round, while Stallings-Mullinax finished the front nine in their second round after an opening 61.

They will complete their rounds when play resumes at 7am (1pm Irish time) on Saturday.