For the second day in a row, the 19th over of the chase proved pivotal to a South African team being knocked out of the Champions League Twenty20. Yesterday, it had seemed all tilted in favour of the bowling side going into the penultimate over - the lethal Dale Steyn (with figures of 3-1-3-1) to bowl against the Trinidad & Tobago lower order, but it was the underdogs from the Caribbean who won, shoving the Cape Cobras out of the tournament.

Today, it was more of an even battle at that stage, with the Warriors having crashed 14 off the previous over to bring the equation to a gettable 23 off 12. With a semi-final place, and the attendant financial rewards, on the line, Somerset's captain Alfonso Thomas bowled a near-perfect over to virtually end South African participation in the CLT20.

He began with a short ball that evaded Craig Thyssen outside off, and then had Thyssen mowing a catch to deep midwicket. There was a single off an inside-edge on the third ball and Wayne Parnell was then fooled by a slower delivery. An almighty heave from a desperate Parnell ended up as a catch to wide long-on before a leg-bye rounded off a two-run over, the least expensive one of the innings.

Thomas' heroics re-affirmed the importance of a solid penultimate over and left the Warriors needing a herculean 21 off the final six deliveries, which proved beyond them. They ended 13 short, and yet again a South African team which made a fast start to a global tournament was eliminated early.

"That's Twenty20 cricket, I suppose," Warriors captain Johan Botha said as they slid out four days after being top of the table, with two victories in two matches. "It can turn very quickly, we had a good start and then we had a bit of a break, five or six days. Pity that it had to end this way, but the other teams played well, we weren't giving guys the result, they just played better than us in the last two games."

Bangalore has typically been the highest scoring venue of the tournament, and Somerset's 146 seemed a below-par effort. Thomas said Craig Kieswetter, who batted through the innings, was "really down on himself" for not pushing the side to a bigger score - but Botha had warned then that it was going to be a tough target to chase.

"The wicket wasn't the best Bangalore wicket we have ever seen, Kieswetter showed his class and set up a good total for them," Botha said after the match. "The wicket almost played like Chennai, if you got behind the rate, it got hard to catch up being really slow. You have got to give credit to the other team, they closed the game out really well."

Somerset became the first English side to make the semi-finals of the CLT20, leaving Thomas full of praise for his side as he singled out 20-year-old debutant Adam Dibble's effort. "He's come in for his first game, went for 13 in his first over and came back and probably bowled one of the better spells of his life (he finished with 4-0-24-1)," Thomas said. "It just shows the character of this team. We came here, nobody gave us a chance, let's face it, but everybody has pulled together and that is exactly what this team is about."

Thomas admitted there was still room for improvement. "We don't want to peak too early like this team has been known to do," he said. "The fielding can certainly sharpen up a bit, but as far as batting and bowling are concerned, we're hitting our straps."

Siddarth Ravindran is a sub-editor at ESPNcricinfo