Chris Gayle gives West Indies a good start to their innings whether opening or chasing. But of late he has been troubled by the ball that comes into his pads © Getty Images

When you're debating the chances of various teams in this World Cup - and there's never any shortage of that before the tournament begins - it's the contests within the contests, the personality clashes, that give you an indication into the kind of trends to expect. Sometimes the fiercest contests aren't between two sets of players who are both at the peak of their game. In this clash between West Indies - resurgent, confident, keen to put up a strong show in the big tournament they are hosting for the first time, and Pakistan - stricken by injuries, forced into selecting certain players, on the downswing rather than up, there are many match-ups that could playa vital role in deciding which way the pendulum of fortune swings.

Mohammad Sami v Chris Gayle

Chris Gayle is unarguably the second most important batsman in the West Indian team. When he gets off to good starts - both batting first and chasing - it gives the others a much better opportunity to express themselves. Unfortunately, in recent times, he has been troubled by the ball that comes into his pads, especially early on in his innings. If you can get him early, you have a good chance of keeping West Indies down to a manageable score. That role would have been assigned to Mohammad Asif, but in his absence it falls to Mohammad Sami. The numbers aren't particularly exciting - 111 wickets from 79 matches at almost 30. But Sami can produce just the kind of delivery that troubles Gayle. Whether he does or not is another matter.

Danish Kaneria v Brian Lara

By some distance the best player of spin in recent times, Brian Lara has torn spinners to shreds so badly at times it has been impossible for the opposition captain to bowl them. To succeed in this World Cup, in these conditions, many experts believe that the spinner's role could be crucial. By no means a certainty in the one-day format, Danish Kaneria could just make a name for himself on pitches that are responsive, as an attacking spinner.

Inzamam-ul-Haq v Marlon Samuels

Thanks to the extended overs of field restrictions, and their floating nature, captains of most teams have targeted the middle overs of an ODI as the place where they can most improve. West Indies have used both Gayle and Marlon Samuels as choking options in this period, and further. Inzamam-ul-Haq, who is the backbone of this Pakistani batting line-up, will have to take control of the game for his side. And this will be determined by how well he can maneuver the ball for ones and twos against the likes of Samuels.

Azhar Mahmood v Shivnarine Chanderpaul

Kamran Akmal's recent poor form with the gloves seems to have affected his bat too © AFP

While Gayle is blasting away at his end, it is left to Shivnarine Chanderpaul to hang in there for the long haul and bat right through the innings. In conditions where the ball will seam about a bit, bowlers like Azhar Mahmood, who rely on variations of pace and cutters of all sorts, could be even more difficult to handle than the ones that are pacy and hit the deck hard. Chanderpaul, though, can cover for all sorts of bowling. How he holds his, and consequently the West Indian innings together, could prove crucial.

Denesh Ramdin v Kamran Akmal

Denesh Ramdin has a fair bit to prove. He's been in and out of the side, and not afraid to voice his disappointment at being left out when this has happened. He's smart behind the stumps and cheeky in front of them. Kamran Akmal has won not just one-day matches but Test matches off his bat in the past. But, in the last year or so, his keeping has fallen away to such an extent that he is missing even straightforward chances, and that has in turn dented his confidence as a batsman. With Abdul Razzaq missing, Akmal will have to shoulder extra responsibility.

Anand Vasu is assistant editor of Cricinfo