THE financial constraints on Clydesdale Bank Premier League clubs has been partly responsible for the increasing trend of plucking players from the lower divisions, but so far it has proved a rich source of plunder.

Paul Dixon crossed the Dundee divide to sign for United last year and has since made 17 appearances in the first team, scoring United's first goal against Celtic at the weekend. Scott Robertson, who made the same journey across Tannadice Street, has been an even more notable success, establishing himself as a first-team regular at United and making his Scotland debut against Argentina in November.

Allan Russell, who switched to Kilmarnock from Airdrie United in the summer, scored his first top-flight goal against Motherwell last month, while Andrew Barrowman made the step up from Ross County to Inverness Caledonian Thistle at the start of the campaign.

Martin Greig looks at seven more who are capable of following in their footsteps . . .

Leigh Griffiths: Livingston
The talented 18-year-old striker is into double figures for the season, despite a remarkable goal splurge at the start of the campaign being followed by injury problems.

The Scotland under-19 striker has had two knee problems but has worked his way back to fitness and is a vital part of Paul Hegarty's plans.

"The boy's got real potential and, as long as we can keep his feet on the ground, he will contribute more often," said the Livingston manager.

Described by previous manager Roberto Landi as an "anarchic player", the teenager has to develop his all-round game if he is to fulfil his potential.

Gary Harkins: Partick Thistle
The 24-year-old midfielder has scored seven goals this season and started to attract the interest of top-flight clubs. Harkins, originally from Greenock, spent six years at Blackburn, rubbing shoulders with the likes of Barry Ferguson, Tugay and David Dunn. He was loaned out to a succession of clubs but failed to break into the first team.

After 12 months at Grimsby Town he finally pitched up at Firhill in the summer of 2007. A rigorous fitness regime has removed some bulk from his imposing frame and allowed him to go box-to-box.

Ian McCall, the Thistle manager, believes he can grace a higher stage. "He is one of four or five players here who are capable of going on to a higher level. He has the potential and he has been great for us this season," he said.

Liam Buchanan: Partick Thistle
He scored 14 goals last season before injury ended his campaign and is an instinctive finisher who is starting to approach his best form after a lengthy lay-off with a groin injury. The vultures have started to hover and the striker has the potential to make the step up.

"Liam is a natural finisher and is like McCoist in that respect," said Ian McCall, his manager. "He is not as good as McCoist yet but he misses a million chances and scores a million chances. He never stops going into the box and putting his body on the line."

Jonny Tuffey: Partick Thistle
Arguably the best goalkeeper in the first division, the Northern Irishman has gone from strength to strength this season. What he lacks in stature, he makes up for in agility and self-confidence.

He made his full international debut in Northern Ireland's 2-0 defeat by Hungary in November, when he took over from Maik Taylor at half time. He turns 22 later this month and has been linked with moves to Rangers, Hearts, Hibernian and Swansea, though Thistle will hope that they can hold on to him for a while longer.

Ryan Stevenson: Ayr United
Started his career as a youngster at Chelsea before moving to St Johnstone in 2002. After failing to establish himself at McDiarmid Park, he signed for his hometown club in an attempt to revive his career. He has scored four goals this season and and may yet be able to step up a level but, at 24, his time is running out.

Murray Davidson: Livingston
His name would not sound out of place in a Frank Hadden Scotland team. His physique, though, is more coatstand than stand-off. That said, Davidson's skeletal frame belies a penchant for a tackle (he was sent off on his debut against Dundee last season and followed that up with a dismissal in his very next match at Morton) and he can be a difficult customer to dispossess.

He has been earning rave reviews in the centre of Livingston's midfield this season and has attracted the interest of Motherwell among other top-flight clubs, who will have been impressed by his assuredness in possession and his ability to keep things simple.

Pat Clarke: Clyde
An ugly duckling during a nascent career spent touring Fife, the 23-year-old is rapidly blossoming into a swan. Tall, angular and leggy, Clarke has scored 14 in 23 games this term for John Brown's side to attract attention from bigger clubs.

Unspectacular spells during the infancy of his footballing life at Dunfermline, Raith Rovers and Cowdenbeath have quickly been forgotten after 12 quietly spectacular months at Broadwood.

Goals in each leg of last season's play-off final win over Airdrie United ensured Clyde's first division status and his exploits this term have attracted the interest of Sheffield Wednesday, Millwall, Hibernian, Motherwell and former side Dunfermline. A six-figure sum may be needed to prise him from the Cumbernauld club.