GLASGOW (AFP) - Rangers maintained their four point advantage at the top of the Scottish Premier League with a 4-2 victory at home to bottom of the table Gretna - to hand manager Walter Smith the perfect 60th birthday gift.

Goals from Gabon international Daniel Cousin, Steven Naismith, Chris Burke and Kris Boyd secured the points for the Ibrox side.

However, either side of Boyd's goal Kenny Deuchar scored twice for Gretna, who battled bravely throughout the match.

At Love Street, meanwhile, Shunsuke Nakamura was Celtic's hero with his late free-kick giving them a vital 1-0 victory over St Mirren.

The Buddies had drawn 1-1 at Celtic Park in December and looked set to further damage the SPL holders title ambitions until the Japanese international struck in the 87th minute.

Back at Ibrox Smith was happy with his side's result but not the performance.

The Rangers boss said: "First and foremost we're delighted we've won the game but also a bit frustrated we were not at our best.

"Our use of the ball could have been better and I'm frustrated at the manner in which we lost both goals as there was a bit of slackness to our defending.

"But after the big UEFA Cup game away to Panathinaikos on Thursday this was a match we just wanted to get through so I'm delighted with the result."

Gretna had came into the game after a week of crisis which saw manager David Irons leave to join First Division Morton, and real fears the club could fall into administration after wages were not paid due to the illness of owner Brooks Mileson.

Rangers quickly added to their troubles by taking the lead in the 13th minute.

Barry Ferguson's header from the halfway line caught out the Gretna defence who allowed Cousin to race in on goal, round goalkeeper Gregg Fleming and tap the ball into the empty net.

The visitor's defence was again posted missing in the 22nd minute when Rangers doubled their advantage.

Ferguson's corner into the six-yard box dropped to Naismith who inexplicably was left unmarked to volley into the net from close range.

Gretna almost pulled one back in the 31st minute when Paul Murray's header struck the post.

However, in the 61st minute Rangers scored a third when French forward Jean-Claude Darcheville crossed for Burke who smashed the ball into the top corner from six-yards.

Gretna continued to battle on and in the 72nd minute they got their reward when Deuchar's diving header, from a Mikael Buscher corner, putting the ball beyond Rangers goalkeeper Allan McGregor.

Rangers restored their three goal advantage in the 88th minute when Steven Davis' slide-rule pass put Boyd, a 61st minute substitute for Cousin, in on goal and he rounded the keeper and slotted home.

However, Gretna again pulled one back a minute later when Buscher's deep corner was headed back across goal by Rhys Meynell and Deuchar nodded the ball into the net.

Gretna's director of football Mick Wadsworth, standing in as caretaker manager was proud of his team's efforts.

He said: "On the back of what's happened at the club in the last week I thought the players were excellent.

"It's a pity we hadn't taken some of chances in the first half but to come here and play the way we did against a club like Rangers was great."

To add further to Gretna's misery second bottom Kilmarnock won 3-1 at home to Aberdeen.

Craig Bryson put Killie ahead in the 14th minute and Frazer Wright doubled their advantage before the break. Bryson completed his brace in the second half, although Darren Mackie scored a consolation for the Dons near the end. str/nr08