Gordon Marshall believes the biggest stumbling block to Celtic winning Sunday's Scottish Communities League Cup final against Kilmarnock at Hampden is Celtic themselves.
Neil Lennon's men are 21 points clear of administration-hit Rangers at the top of the Clydesdale Bank Premier League and kept themselves on course for the treble yesterday with a 4-0 win over Dundee United in the William Hill quarter-final at Tannadice.
Marshall has experience of playing in finals with both Kilmarnock and Celtic, having kept goal for the Hoops side which infamously lost on penalties to First Division Raith Rovers in the 1994 League Cup final at Ibrox.
In 2001, he was playing for Killie when Henrik Larsson scored a second-half hat-trick to land Martin O'Neill's first trophy in the Irishman's debut season.
And speaking at Hampden today where he was helping to publicise the upcoming final, Marshall, currently goalkeeping coach at Motherwell, claimed Celtic, who are unbeaten in 26 domestic games since losing 2-0 to Hearts at Tynecastle in October, have to guard against complacency.
"Celtic have got to be favourites, they are certainly the best team in Scotland just now and playing well going into the final," he said.
"Obviously the league looks as if it is going to take care of itself so they have to go for the two cups to get the clean sweep.
"The only problem Celtic might have is Celtic.
"They have got to make sure they have the right attitude.
"When I was in the Killie team who played them here, Larsson was probably the only one who was scoring goals at the time.
"Now they have Stokes, Hooper and Samaras and they have been scoring a lot more from all over the park so I think Celtic's biggest problem is going to be Celtic.
"But Lennon and his staff know what it's like to turn up for these big days and I'm sure they will be well prepared.
"Celtic have been down this road before, the Kilmarnock guys will need to be aware of the distractions, how many tickets they will get, what is their bonus and things like that.
"Hopefully they have all that organised so they can concentrate on playing.
"It will be exciting for people behind the scenes, it's a wonderful day out for them.
"I had a wee taste of that 11 years ago, it was a fantastic final from that side of things.
"But when it comes to the football, I think Celtic are going to be the stronger of the two.
"I think Kilmarnock will need to start well and score first because if you let Celtic score they become a difficult team to get two goals against.
"Kilmarnock will want to stay in the game as long as possible and the longer it goes on, maybe that the thing that agitates Celtic a wee bit."
While a Killie victory would be a shock, it would not come into the same category of cup final upsets as Raith's finest hour.
To that end, Marshall warned Celtic players that defeat may take some time to live down.
"Yes, I get a wee bit of stick now and again," he said.
"The club steward where I play golf is in charge of the Raith Rovers supporters club, so I still get a wee reminder now and again.
"But my skin is a lot thicker now, after playing the number of games I have played.
"The big thing with Celtic is you have to win every game and it's that mentality of win, win, win.
"So yes, there will be a lot of stick if Celtic don't win it but that won't be in the players' minds.
"They have been very ruthless recently so they will go in with the right frame of mind."