Closing in on the semi-finalists

Chennai Super Kings have jumped to second spot with 16 points, and though they aren't completely certain of a place in the last four, they're very well placed because of their excellent net run-rate of 0.544. The only team that can eliminate them are Punjab, whose NRR is languishing at -0.183. Even if Punjab win their last two games by 40 runs and if Chennai lose theirs by the same margin, Chennai's NRR will still be 0.01 ahead.

Mumbai Indians were the runaway leaders through the first two-thirds of the tournament, but two losses in a row have made their case trickier than most would have expected. The 87 all out against Punjab has also adversely affected their NRR, pushing them below Chennai to third place. Given that Mumbai's last game is against Kolkata at Eden Gardens, their best chance to seal their case will be their next match, when they play beleaguered Rajasthan at home.

However, if Mumbai lose both their matches their qualification could depend on run rates. For that to happen, Punjab will need to win both their matches, and Kolkata will require at least one win out of two. If Mumbai lose both their games by 30 runs chasing 160, and if Punjab win their games by 20 runs, then Punjab will sneak ahead by 0.001. If the margins aren't so convincing, Mumbai will scrape through even if they lose their last two.

Kolkata Knight Riders are currently in fourth place, and they need to win at least one of their last two matches to make their position fairly secure. It helps that their NRR is a healthy 0.403, which is much better than Punjab's.

However, if Kolkata lose both their games, they could be under threat from three teams - Punjab, Pune Warriors and Kochi Tuskers Kerala. Of those three teams, Kochi's chances are the weakest, since they have a NRR of -0.186 with only one game to go. Pune, though, could go past Kolkata if they win their last three and if Kolkata lose two (see Pune's case below).

Kings XI Punjab have made a late resurgence, winning three on the trot to suddenly revive their campaign. Given their poor NRR of -0.183, though, they'll almost certainly need wins in their last two games to stand a chance of making the cut. Even then, they'll need other results to go their way, for if Kolkata win their last two, and if Mumbai and Chennai win a game each, even 16 points won't be enough for Punjab.

Pune Warriors are the only side who have three matches to play, and if they make the best use of those chances, they could well come into the reckoning. If, for instance, Pune win all three, they'll finish with 14 points, which will give them a chance if Kolkata lose their last two and if Punjab don't win both their games.

Pune's case is also strengthened by their relatively strong NRR: it's currently -0.003, which is pretty good for a team with seven defeats and only four wins. For simplicity's sake, let's assume they win each of their last three games by 20 runs after scoring 160, and Kolkata similarly lose their last two by 20 - then Punjab's NRR will be 0.225 and Kolkata's 0.185. Punjab's current NRR is -0.183, and if they win a game and lose one (to get to 14 points), their NRR is unlikely to get anywhere near those of Pune or Kolkata.

Kochi Tuskers Kerala have a mathematical chance of making the top four, but their NRR is much worse than Kolkata's, the only team they can topple. Their only chance is if they win their last game by a huge margin, and if Kolkata lose both their matches convincingly: a margin of about 45 runs in each of those matches will push Kochi marginally ahead of Kolkata, but if the margins aren't so substantial Kochi's game against Chennai will be their last one in IPL 2011.