'I had my European Tour card in 1984 but unfortunately never used it because I got my U.S. card as well, but we've had a great time in Stockholm,' said Sluman, who is playing in his first European Tour event outside the British Open. 'It's been a wonderful experience and I hope I can finish it off with a win.'
Fasth, the world's top-ranked Swede at No. 32 in the official rankings, turned in a 65. He mixed three bogeys throughout his round but countered with five birdies and a pair of eagles, his last coming on a 15-foot putt at the 17th.
McDowell, a rookie from Northern Ireland who led after the first round, rebounded from shooting a 2-over 73 Friday with a 5-under 66.
'Today I was much more relaxed and had fun out there,' said the former standout at the University of Alabama-Birmingham. 'It helped being in the third-to-last group and it will help not being in the last group as well on Sunday.'
After carding birdies on the 16th and 17th, former South African Amateur champion Trevor Immelman just missed a 10-foot birdie try at the final hole that would have lifted him into the logjam in first place. He tapped in for his second straight round of 67 at Kungsngen Golf Club and sole possession of fourth at 9-under par.
Overnight leader Warren Bennett recovered from a wild tee shot to birdie a hole for the second day in a row, but his bid for a better round was foiled by a balky putter. The Englishman shot 69 and dropped into a tie for fifth at 8-under 205 with Norway's Henrik Bjornstad (66), and the Swedish duo of Carl Pettersson (68) and Fredrik Andersson (68).
Colin Montgomerie, the defending champion seeking his fourth victory in this event, began the third round only three strokes off the lead. However, the burly Scot rang up a triple-bogey six at the par-3 16th on his way to a 3-over 74, knocking him back to even par for the tournament.
Sluman, two shots back to start the day, produced three birdies on each nine. He birdied all three of the par-5s including the 520-yard 17th, where he reached a greenside bunker in two and blasted out to easy birdie range.
The 1988 PGA Champion is in position to win his second title of the 2002 season. He posted rounds of 64-66-63-68 en route to a four-stroke victory at last month's Greater Milwaukee Open.
Sluman's decision to enter the field for the Scandinavian Masters was made easier due to the fact he was already scheduled to be in Sweden to attend the wedding of Jesper Parnevik's sister Jill to Per-Ulrik Johansson.
'Jesper's been trying to get me to come over for the last few years but the wedding clinched it,' said Sluman, whose wife Linda is half-Swedish.
'A Swedish wedding is a little different from an American one, but it's something I will always remember.'
Johansson celebrated his recent nuptials by setting a new Kungsngen course record Saturday with an 8-under-par 63. He broke the previous mark of 64 established by McDowell in the opening round.
'I'm a very happy man,' said Johansson, who birdied the 17th Friday to make the cut by one shot. Saturday's 63 pulled him within four strokes of the lead at 6-under par.
'My slow start was more down to the fact that I am really tired and I haven't practiced much, so I wasn't really into the first two rounds.'
Parnevik rolled in a 20-foot putt on the 18th for his third consecutive birdie to close his round. He shot a 68 to finish at minus 5.