The Scottish Rugby Union have introduced a `golden try' rule which means there has to be a winner in Saturday's BT Cellnet Cup, Shield and Bowl finals.

Like last season's end-of-season event at Murrayfield, if the scores are level at full-time there will be a period of extra-time of 10 minutes each way.

If this does not produce a result the trophies will go to the teams who have scored the most tries, conversions and then drop-goals.

If any sides are still undivided there will be a further period of play and the first team to score a try will be the victors.

John Thorburn, the SRU's manager of the domestic game, explained, "There will be some changes in the rules from last year and it will effect what happens in the finals of the BT Cellnet Bowl, Shield and Cup should it finish as a draw.

"If the scores are level at full-time there will be extra-time with a one-minute interval.

"Just like last year if the teams are tied at that point there are three criteria to determine the winners.

"Firstly the team scoring the more tries, secondly the team scoring more conversions and thirdly the team scoring the more drop-goals.

"If the teams are still tied at that point we have a slight change of rules from last year when the match would be declared as a draw and the trophy shared.

"Now we'll have a sudden death extra time during which the team scoring first will be the winners.

"I don't know whether anyone will have any nerves left after all that should we reach that stage but I'm sure it will add to the excitement of the BT Cellnet Cup carnival."

Boroughmuir team for BT Cellnet Cup final: Tom Lightoller, Derek Stark, Lindsey Graham, Graeme Kiddie, Rory Couper, Calvin Howarth, Douglas Roberts, Alan Green, David Cunningham, Sandy Penman (capt), Alastair Davidson, Graeme McCallum, Nigel Bruce, Rob Muir, Oliver Brown.

Replacements: Neil Dickson, Danny Rutterford, Euan MacDonald, John McKinley, Calum Cusiter, Mark Murray, Tony Dowling,

Glasgow Hawks team: Campbell Aitken, Kenny Baillie, Chris Simmers, Ricky Munday, Gerry Hawkes, Eugene Martin, Cameron Little, Connel Hanvey, Chris Docherty, Gavin Walsh, Charles Afuakwah, Ian Smith, Scott Hutton(captain), Robert Niven, Rory McKay.

Replacements: from Liam McIntyre, David MacNeil, Kevin Horton, Greg Francis, Paul Reid, Steven Winters, Kenny Sinclair, Torquil Mathewson, Nicky Barret.

Glasgow Southern team for BT Cellnet Shield final: Ally Menzies, Andy Richardson, Ross Armour, Scot Gerry(captain), Michael Loakman, Andy Healy, Iain Monaghan, Zander McIlwham, Euan Bennett, Gavin Blackburn, Andy Tunn, David Cobban, Jan Vos, Darren O'Reilly, Ritchie Nolan.

Replacements: Glen King, Garry Blackadder, Charlie Goldie, Kevin Devlin, Paul Devlin, Dominic Sharkey, Craig Kennedy.

East Kilbride: Hayden Pitcher, Gordon Steven, Colin Bartwicki, Craig Redpath, Graeme MacAllister, Andrew MacDonald, Robert Guthrie, Rian Anderson, Andrew Welsh, Colin Stewart, Craig Houston, Gordon Ferrie, Glen Tippett, Peter Pattenden (captain).

Replacements: Scott Turnbull, Stewart Leggat, Craig Steven, John Watson Stuart Bartwicki, Graeme Blackwood, Ian Thompson.

Linlithgow team for BT Cellnet Bowl final: Matthew Dixon, Atholl Bowman, Mark Bonnar, Jason Wright, David MacKenzie, John Smith, Kenny Harper, John Gibson, David Cairns, Bryan Cherrie, Scott Waddell, Stuart Jamieson, John Scobbie, Gavin Spowage, Grant Hotson.

Replacements: Gregor MacKenzie, Steve Matthews, Rickard Armer, Douglas Wood
Scott Oliver, Iain Taylor, Douglas Galloway.

Murrayfield Wanderers: Jack Cadell, Adam Broatch, Drew Miller, Graeme Jessop, Chris Dove, Christian Bruce, Gary Donaldson, Steve Cully, Donald Terris, Mike Pender, Dave Sullivan, Mike Christie, Greg Adams, George Sutherland, Neil McCallum (captain).

Replacements: Dan Lunnon-Wood, James Beattie, Neil Earnshaw, Alan Shaw, Phil Duguid, Gordon Cuthill, Rory Taylor.