Reigning champions England maintained their bid to reach the second round of the T20 World Cup with a 41-run victory in a must-win group game against Namibia in Antigua on Saturday.

Anything other than an England win would have seen Jos Buttler's men knocked out and they were left fearing an early exit when rain delayed the scheduled start by three hours.

England, in a match eventually reduced from 11 to 10 overs per side by a fresh shower, collapsed to 13-2 after losing the toss.

But a stand of 56 between the Yorkshire duo of Harry Brook (47 not out off 20 balls) and Jonny Bairstow (31) helped take them to a total of 122-5.

Namibia were left with a target of 126 under the Duckworth-Lewis-Stern method for rain-interrupted matches.

But they were never up with the required run-rate against England's new-ball duo of Reece Topley (0-6 in two overs) and Jofra Archer (1-15), with the non-Test nation finishing on 84-3.

Victory took England level on points with Scotland in Group B but with a superior net run-rate.

- 'Anxiety' -

England, however, could still miss out on the Super Eights should Scotland achieve a stunning upset win over already-qualified Australia in the Group B finale in St Lucia later Saturday, or if that game ends in a no-result.

"There was a lot of anxiety, we didn't think we'd get out there," said Brook, the player of the match. "Thankfully the rain stopped."

England captain Buttler, bowled for a duck, said: "It's a big relief.

"It's been a stressful day with the rain coming down, but I think we put in a really good performance."

He added: "I thought that was a really good score on that wicket. When I got out I thought 85-90 might be a good score.

The already-eliminated Namibia retired opener Nikolaas Davin out for 18 to allow the big-hitting David Wiese to come in at 44-1 off six overs.

But even with the 39-year-old Wiese -- who holed out in the last over of his final international appearance -- striking two sixes and two fours in a 12-ball 27, Namibia finished well-short of their target.

"It was a steep chase, but felt bowling first was the right way to go," said Namibia captain Gerhard Erasmus.

"Wiese doesn't want to open, next time we'd get him in earlier, but unfortunately it was his last game... Massive impact, in terms of the level of cricket he brought to our circle, he inspired us to new heights."

Earlier, Ruben Trumpelmann bowled Buttler, one of the world's best white-ball batsman, for nought as he nipped one back sharply off the pitch.

Veteran all-rounder Wiese then produced a magnificent slower ball to have Phil Salt, England's other opener, caught behind.

Rain stopped play with England 82-3 off eight overs.

When the match resumed, Brook did the damage in an over from teenage paceman Jack Brassell that cost 19 runs.

Moeen Ali and Liam Livingstone then struck three sixes between them in the last over from Trumpelmann, who took 2-31.