VILAMOURA, Portugal, Oct 13, 2012 (AFP) - The New Zealander will go into Sunday's final day just four shots behind leader Bernd Wiesberger of Austria after firing a third-round 67.
Campbell is now down at 607 in the world rankings, having not had a top-10 finish on the European Tour since 2008. In 2010, he made only one cut in 19 starts.
"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 Sunday," said Campbell, who is on nine-under-par 204 for three rounds.
"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."
Campbell shares third place with Irishman Shane Lowry and England's Richard Finch, but it could have been better for the Kiwi had he not bogeyed the last hole.
Six birdies in seven holes around the turn helped Wiesberger claim a one-shot lead for the tournament.
The Austrian, already a two-time winner this season, had all his birdies between the eighth and 14th holes in a bogey-free round of 65.
He will start Sunday's final round on 13 under par, one shot ahead of overnight leader Ross Fisher of England.
"After seven holes I was not thinking about a 65," admitted Wiesberger.
"I hit some poor wedges early on, but I grinded through that and hit better shots around the turn and into the back nine."
Spain's Miguel Angel Jimenez, 48, and trying to become the oldest winner in European Tour history, finished with a 30-foot birdie putt for a round of 68, and is five shots off the pace.
Leading and selected third round scores of the Portugal Masters at the Oceanico Victoria golf course on Saturday (par 71, GBR/IRL unless stated):
200 - Bernd Wiesberger (AUT) 70-65-65
201 - Ross Fisher 65-67-69
204 - Michael Campbell (NZL) 68-69-67, Shane Lowry 67-70-67, Richard Finch 70-68-66
205 - Miguel Angel Jimenez (ESP) 69-68-68, Mark Foster 71-67-67
206 - Christian Nilsson (SWE) 67-70-69, Andrew Dodt (AUS) 72-70-64, Gonzalo Fdez-Castano (ESP) 68-71-67, Fredrik Andersson Hed (SWE) 67-69-70
207 - Anthony Wall 68-71-68, George Murray 66-76-65, Stephen Gallacher 65-70-72, Richard Green (AUS) 70-68-69, Markus Brier (AUT) 69-71-67, Padraig Harrington 69-67-71
208 - Francesco Molinari (ITA) 71-71-66, Thomas Aiken (RSA) 68-71-69, Peter Whiteford 70-71-67, Marcel Siem (GER) 72-68-68, Keith Horne (RSA) 69-72-67, Lorenzo Gagli (ITA) 72-69-67, Henrik Stenson (SWE) 70-70-68, Oscar Floren (SWE) 73-68-67
209 - Ricardo Gonzalez (ARG) 69-72-68, Andy Sullivan 72-69-68, Ricardo Melo Gouveia (POR) 70-72-67, George Coetzee (RSA) 69-73-67, Scott Jamieson 71-70-68
Selected
210 - Hennie Otto (RSA) 70-71-69
211 - Shaun Micheel (USA) 74-68-69
212 - Matthew Zions (AUS) 70-72-70
213 - Thomas Bjorn (DEN) 70-70-73, Rich Beem (USA) 70-72-71
215 - Jbe Kruger (RSA) 67-71-77