Ireland's Shane Lowry and Graeme McDowell came out all guns blazing in the final round of the QBE Shootout, but they were beaten to glory by Steve Stricker and Sean O'Hair, who clinched the title by two shots following a flawless eight-under-par.

Lowry and McDowell, and American pair Stricker and O'Hair, started the day with a share of the lead at 18-under-par after the first two rounds - the opening round under a scramble format and the second played under greensomes rules, a modified alternate-shot format.

The final round was played in a better-ball format, where only the best score from either player is counted, and both groups opened up with a birdie on the first hole of the Gold Course at the Tiburon Golf Club.

The American duo continue their gain trail with three-successive birdies to turn in a score of 32 but Lowry and McDowell fought back.

The Irish pair, who did not drop a single shot over the three rounds, matched their American counterparts with four gains to maintain their share at the top of the leaderboard with 22-under-par at the halfway point.

Further gains at the 11th and 14th saw Stricker and O'Hair lead by two, and - despite Lowry and McDowell halving the deficit at the next with a birdie - the Americans carded a magnificent eagle on the par-five 17th to put the Irishmen out of reach.

Lowry and McDowell finished in style with their sixth birdie of the round but a par from Stricker and O'Hair was enough to secure the title with a score of 64.

Zach Johnson and Charley Hoffman produced the round of the final day with a stunning 63, finishing their final six holes with one par, four birdies and an eagle for a unblemished nine-under-par to come home eight shots off the lead.

Four shots better off, Pat Perez and Brian Harman finished third at 22-under-par, while Brendan Steele and Keegan Bradley, Gary Woodland and Daniel Berger and Lexi Thompson - the only woman in the field - and Tony Finau finished a further shot adrift in a three-way tie for fourth.