By Ray French BBC rugby league commentator

Trent Barrett is a major threat for Wigan

Challenge Cup ties between Widnes and Wigan are steeped in history.

Previous ties between the Lancashire rivals have seen the two clubs playing at the peak of their profession with some of the greatest players in the world going head-to-head.

In fact, apart from their first meeting in 1936, every time these clubs have met in the Challenge Cup in a round other than the final, the winner has gone on to reach the final.

Today though things are very different with Wigan steadily recovering after a shocking season last year, whilst Widnes are preparing for another tilt at promotion back to the Super League.

There's a whiff of an upset in the air, but I fully expect Wigan to be the team that takes a step closer to the final at Wembley when they clash on Sunday, live on BBC TWO.

The key to the game will be Wigan's two half-backs, Trent Barrett and Thomas Leuluai.

WIDNES v WIGAN Sun 1 April, 1430 BST BBC Two and the BBC Sport website

If they play to the standard they have done in recent weeks, Widnes may struggle to cope.

It will be a similar story in the pack - Stuart Fielden and Iafeta Palea'aesina will be too big, too powerful, too strong and too fit for Widnes, so it should be a comfortable win.

The one thing Widnes do have in their favour though is the staggering fact that they will have nine former Wigan players in their squad.

The likes of Mark Smith, Mick Cassidy and Dennis Moran have a tremendous incentive to prove Wigan's management wrong for selling them and that's a huge motivating factor.

Often when you face a team containing so many of your former players it can prove to be very difficult and that's what Wigan will have to deal with on Sunday.

Warrington v Hull KR is the other televised game on BBC ONE on Saturday and it is a pretty well matched fixture.

The absence of Lee Briers is a major blow for Warrington

Warrington would normally be clear favourites, but their big problem is that they have one million pounds' worth of talent missing for this game thanks to injuries to Adrian Morley, Lee Briers and Paul Johnson.

Half-back Briers is one of the most prolific point scorers in their history and they will sorely miss his passing and movement.

Warrington are absolutely reeling from these injuries, which makes it much more of proposition for Hull KR, especially as the Wolves are such an inconsistent side who tend to win one game then lose the next.

Hull KR are a very enthusiastic and spirited outfit that have no superstars.

Many of them honed their skills in National League One last year and the biggest plus they've got is that coach Justin Morgan maintained his loyalty to two-thirds of his squad after they got promotion.

Normally when you get promotion to the Super League you buy a new team, but he didn't, he kept faith with his team and I think they are giving him back that spirit and loyalty.

WARRINGTON v HULL KR Sat 31 March, 1415 BST BBC One and the BBC Sport website Forum on BBCi at 1630

Don't be surprised if Hull KR cause an upset in this game although it depends how seriously Morgan decides to take it.

He told me last week that his major priority is staying in the Super League, but such is the profile and publicity they got from their win last year against Warrington, a similar thing this time round will really enhance the club so it puts him in two minds.

I think they will give it a go for 40 minutes and if they are still in it at half time it will be a very difficult game for Warrington.

In the other ties, there isn't much potential for shocks because the big teams have all been drawn at home.

St Helens should run up a cricket score against Batley and the likes of Salford and Leeds should cruise through.

The good news about this though is that it ensures that there will be some very competitive ties in the fifth round.