Shane Watson notched his maiden international century as Australia crushed the West Indies by seven wickets in the third One-Day International at Grenada's National Stadium Sunday. The victory gave Australia an insurmountable 3-0 lead in the five-match series, after it won opening match by 84 runs last Tuesday at the Arnos Vale Sports Complex, and the second ODI by 63 runs under the Duckworth-Lewis Method last Friday at this venue. It also makes dead rubbers of the final two matches in St. Kitts, scheduled for later this week. Save for Fidel Edwards' early dismissal of Shaun Marsh for a duck, the hosts never seemed close to defending their total of 223. Watson and Ricky Ponting posted a 190-run stand, the highest ever limited overs second-wicket partnership by an Australian pair in the Caribbean, as the tourists rolled to 227 for three in 40.3 overs. Watson's innings of 126 from 122 deliveries was his first century in any form of international cricket, and came more than six years after his one-day debut for Australia. The Queensland all-rounder has suffered a horrendous run of injuries over the course of his career, and was only called into the Australian squad as a late replacement for Matthew Hayden. Watson raised his century with a boundary through mid-wicket off the bowling of Chris Gayle. He was embraced by his capatin, Ponting, who was eventually dismissed by Gayle for 69, though not before he had steered Australia to the cusp of a commanding victory. On a slow pitch, Watson displayed patience and poise in the early stages of his innings before accelerating later. The right-hander was particularly damaging square of the wicket, striking sixes over mid-wicket and wide long-on during his career-best innings. Watson was removed attempting to paddle Darren Sammy down the leg side in the 37th over. The home supporters were left disappointed by another underwhelming performance from the West Indian team. Among the hosts' bowlers, only Edwards and Dwayne Bravo threatened for extended periods, and the Windies' energy levels in the field appeared to be lacking, as evidenced by a number of dropped catches and misfields throughout the Australian innings.