Graeme McDowell and his partner Matt Wallace slid down the leaderboard after the third round of the Zurich Classic of New Orleans on Saturday.

Playing a best-ball format, McDowell and Wallace carded a respectable four-under 68 but the bar was high on a day of low scoring.

FULL LEADERBOARD

They are in a tie for 25th on a total score of 204 (12-under), with the leaders Louis Oosthuizen and Charl Schwartzel on 197 (19-under).

Oosthuizen and Schwartzel shot a brilliant nine-under 63 to surge into the lead.

The South African pair had kept themselves in contention with a 63 in the four balls and 71 in the foursomes going into the weekend, and carded another 63 on Saturday to take a one-shot lead.

They reached the turn in three-under 33, and had two runs of three-straight birdies coming back to sit 19-under in Louisiana.

At their heels are Australian pair Marc Leishman and Cameron Smith who also signed for a 63, while overnight joint leaders Tony Finau and Cameron Champ are also on 18-under after a round of 67.

Norwegian pair Viktor Hovland and Kris Ventura, who also had the joint lead going into Saturday, went round in 68 and have a share of fourth.

The two-man event will adopt a fourball-style format for Sunday's final round.