Two games, 160 minutes, bragging rights for a year.

Oh, and maybe a Scotland place on the line as well. The Heineken Cup may be over for Edinburgh and Glasgow already, but the stakes are still high as their back-to-back derbies loom.

It was not always thus. As its name suggests, there is 140 years of history behind the 1872 Cup, but it is only over the past few years that it has really acquired much bite. The home-and-away format over the festive period has been a marvellous innovation. If players don't go into the first game with scores to settle, they certainly have some on board by the time the second match kicks off.

Home advantage has been the most telling factor in recent seasons. Only one of the past 18 matches has produced an away win. It would be an act of boldness to bet against that trend continuing this year, with the two sides looking as well-matched as ever. Or, given their Heineken Cup performances, just as bad as each other.

Glasgow coach Gregor Townsend has been coy about Al Kellock's recovery process since the lock sustained a serious cut to his arm just over a week ago. If they can get him on the pitch then Glasgow's prospects improve significantly, as few players have ever poured heart and soul into this fixture the way Kellock does.

It all kicks off at Scotstoun on Friday. For once, the players will be able to enjoy a civilised Christmas as the return match at Murrayfield is eight days later. So where will the critical edges be found? Who will enjoy the best of times in our tale of two cities this year?

Set-Piece

The days of powder puff Scottish packs are long gone. Edinburgh and Glasgow have evolved their scrums as powerful attacking weapons and both can field all-international front rows. The massive Yorkshireman Mike Cusack has been a revelation at tighthead for Glasgow this season, while Willem Nel is finally starting to live up to his billing in the Edinburgh No 3 shirt.

Edinburgh hooker Ross Ford has been out of sorts this season. He looked more like his usual self against Racing Metro on Friday, but his line-out work was still suspect. However, Glasgow will be weakened if lock Al Kellock does not recover from an arm injury in time. Kellock relishes the Inter-City games like few others and his appetite and leadership skills will be missed if he is not involved.

Strike Runners

Both teams are picking from strength this year and they have pace and power to spare in the wing positions. Edinburgh's Tim Visser is arguably the best finisher in the British Isles, and he should be fresh again after missing this weekend's round of Heineken Cup matches. Lee Jones has also timed his comeback from injury just right.

For Glasgow, DTH Van der Merwe and Tommy Seymour have been running tries in for fun at times, while they also have the power of Sean Lamont on tap. Stuart Hogg has looked a little lost in the centre, but if the game starts to break up then he becomes a danger man as well.

Playmakers

A problem area for both sides this season. At Glasgow, coach Gregor Townsend has used Ruaridh Jackson, Duncan Weir and Scott Wight at fly-half over the past couple of months, but none has really nailed the position down as his own. On recent form, Wight looks to be the best of the bunch.

Edinburgh's Greig Laidlaw seemed to struggle in the Scotland No 10 shirt during the November Tests and still lacks the kicking game to be considered a complete player in the position. Coach Michael Bradley called on newcomer Piers Francis against Racing Metro on Friday evening, but he kicked poorly and it would be a bold decision to pitch him into the febrile atmosphere of the 1872 Cup.

Line Breakers

With both teams boasting such firepower on the wings, what happens in the midfield could be the critical factor. Edinburgh appear to have the upper hand in the shape of current Scotland pairing Matt Scott and Nick De Luca, but Glasgow's Peter Horne has made huge strides this season and is knocking on the door of international selection. Stuart Hogg has been quiet in the No 13 shirt, but he can still be a devastating runner.

Defensively, Edinburgh look stronger as well, although they have had some horrible moments this season, particularly in their early Heineken Cup matches.

The Breakdown

Winning the collisions is the key to winning rugby matches these days. Only a couple of seasons ago, Glasgow were rampant in that area, with their Brown/Barclay/Beattie back row dominating games. John Barclay is the only survivor from that group, and his form has dipped this season. Glasgow are now better at slowing down opposition ball than making something of their own possession.

If Edinburgh can work up a head of steam, they could find a critical advantage through players such as Dave Denton, Stuart McInally and Netani Talei. They also have the wonderfully stroppy Sean Cox, as well as the fast-improving Grant Gilchrist, in the second row. In recent seasons the Glasgow pack has been the more effective of the two, but they will miss Kellock if he is ruled out this year.