Shane Watson and Mike Hussey smashed half centuries to lead Australia to a convincing eight-wicket win over West Indies in the first Twenty20 international at St Lucia on Tuesday.

Watson hit 69 off just 43 balls, including five fours and six sixes, and Hussey finished unbeaten on 59 from 45 deliveries.

Set 151 to win after West Indies made 150 for seven from their 20 overs, the Australians reached their target with 11 balls to spare to go one-up in the two-match series.

"It's nice, good to be able to put a complete performance together," Watson said in a televised interview.

"I was thinking 160-170 was a par score, it's a beautiful wicket and a pretty small boundary as well, so we thought 150 would be good to chase."

Kieron Pollard top-scored for the home team with a ferocious unbeaten 54 off just 26 balls, the fastest ever half-century by a West Indian in T20s, highlighted by five massive sixes.

Australia made an awful start to their reply when they lost Dave Warner for a duck in the first over but Watson and Hussey safely steered them to victory with a second-wicket partnership of 108.

West Indies skipper Darren Sammy said his team needed to score at least 20 more runs and would consider making changes.

"We were looking for about 170 but the Australians bowled well and maybe outplayed us today," he said.

"We have one more game in Barbados and hope to change things there. We might try to add some firepower to the bowling for the next game."

Scoreboard: 

West Indies 
 J.Charles lbw b Watson                 24 
 D.Smith c Wade b Lee                   10 
 N.Bonner b Christian                   24 
 Darren Bravo c Pattinson b Christian   12 
 K.Pollard not out                      54 
 Dwayne Bravo c D.Hussey b Christian    14 
 D.Sammy c D.Hussey b Lee                7 
 C.Baugh run out                         1 
 G.Mathurin not out                      1 
 Extras (lb-1 w-2)                       3 
 Total (for seven wickets, 20 overs)   150 
Did not bat: K.Santokie, S.Narine 
Fall of wickets: 1-19 2-38 3-66 4-72 5-134 6-144 7-148 
Bowling: B.Lee 4-0-30-2 (w-1), J.Pattinson 3-0-21-0 (w-1), C.McKay 3-0-21-0, S.Watson 4-0-16-1, X.Doherty 3-0-34-0, D.Christian 3-0-27-3 

Australia  
 D.Warner b Santokie                     0 
 S.Watson c Pollard b Mathurin          69 
 M.Hussey not out                       59 
 G.Bailey not out                       21 
 Extras (lb-1 w-2 nb-1)                  4 
 Total (for two wickets, 18.1 overs)   153 
Did not bat: M.Wade, D.Hussey, D.Christian, C.McKay,
X.Doherty, B.Lee, J.Pattinson Fall of wickets: 1-0 2-108 
Bowling: K.Santokie 3-0-27-1 (w-1), G.Mathurin 4-0-33-1 (nb-1, w-1), S.Narine 4-0-21-0, D.Sammy 2.1-0-22-0, Dwayne Bravo 3-0-21-0, K.Pollard 1-0-16-0, D.Smith 1-0-12-0 
Result: Australia won by eight wickets 
Man of the match: Shane Watson (Australia)