Kiwi Michael Campbell in contention at Portugal Masters

(CNN) -- Former U.S. Open champion Michael Campbell is enjoying a welcome return to form at the Portugal Masters after a third round 67 left him tied for third place heading into Sunday's final round.

Since winning at Pinehurst in 2005, the New Zealander has endured a wretched run of form and is currently ranked 607th in the world. His last European Tour victory was at the HSBC World Match Play Championship at Wentworth in the same year as his only major triumph.

"It's seven years since my last win and I was surprised how calm I was out there, but I've won enough around the world to know what to do, and I'm pretty excited about tomorrow," Campbell said.

"Over the last three or four years, I've put too much pressure on myself to perform. I've gone back to basics, and it's fun once again," he added.

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The 43-year-old hasn't recorded a top ten on the European Tour since 2008 and in 2010 made just one cut in 19 starts. At the same tournament two seasons ago Campbell was ranked equal 1325th.

After rounds of 68 and 69 on Thursday and Friday, Campbell bagged five birdies on Saturday at the Oceanico Victoria Golf Course on the Algarve. The only blemish coming with a bogey at the last to leave him on nine-under par.

Ireland's Shane Lowry also shot a 67 to finish on the same score while England's Richard Finch is also nine under after an impressive third round 66.

The trio are three shots behind second-placed Ross Fisher, who is 12-under after carding a 69, and four off the leader Bernd Wiesberger.

Six birdies in seven holes helped the Austrian post a second consecutive round of 65, leaving him one clear on 13-under par.

"I played beautifully on the back nine, and I could've gone even lower," Wiesberger said.