Australian Steve Allan has flashed home for fourth at the US PGA Tour Viking Classic at the Annandale Golf Club in Madison, Mississippi. Allan finished three shots off a trio at the head of the leaderboard after following up his third-round 67 with a blistering 66 on the final day. Will MacKenzie birdied the second hole of a three-man play-off. MacKenzie, Brian Gay and rookie Marc Turnesa each finished regulation play at 19-under-par 269, with MacKenzie and Gay each posting a four-under 68 in the final round. Turnesa threw away a three-shot lead on the back nine. He couldn&apost turn it around in the sudden-death shootout with MacKenzie securing his second career win. Gay was eliminated at the first play-off hole when he bogeyed the par-four 18th as MacKenzie and Turnesa each posted a par. Allan was locked with Americans Bill Haas and Casey Wittenburg in fourth. The Australian was the only non-American in the top dozen. His countryman Nathan Green signed for a 68 on Sunday to be 10-under-par for the tournament. Fourth Round of the Viking Classic, Madison, USA -19: Will MacKenzie 70 64 67 68 (won by playoff), Marc Turnesa 65 68 66 70, Brian Gay 66 68 67 68 -16: Steve Allan (Australia) 71 68 67 68, Bill Haas 69 69 66 68, Casey Wittenberg 68 67 68 69 -15: Greg Kraft 68 69 68 68 -14: Woody Austin 69 69 67 69, Brad Elder 68 68 69 69, Jason Gore 71 69 68 66, Dicky Pride 67 67 68 72, David Toms 69 68 71 66 -13: Tome Scherrer 69 72 66 68 Also: -10: Nathan Green (Australia) 67 73 70 68 -7: Gavin Coles (Australia) 71 69 71 70 -6: Andrew Buckle (Australia) 67 71 73 71 -5: Nick Flanagan (Australia) 68 74 70 71