Red Bull driver Sebastian Vettel won the Singapore Grand Prix for the second straight year on Sunday, jumping up to second place in the Formula One drivers' championship.

Vettel inherited the lead from pole-sitter Lewis Hamilton of McLaren, who led the race until he suffered a gearbox failure on lap 22 and had to retire.

It was defending champion Vettel's second win of the season after Bahrain.

"We benefited a little bit from Lewis' failure,'' Vettel said.

"We had a very, very strong pace all weekend and a good start, which got us in the hunt.

"I am just incredibly happy and proud.''

Gearbox issues

Hamilton's gearbox was leaking fluid for three to four laps before he retired. As his car came to a halt, team officials told Hamilton over the radio that "we did everything we could yesterday'' - suggesting the team had gone into the race knowing there was an issue, but was unwilling to take a five-grid-place penalty for changing the gearbox before the race.

Hamilton's teammate Jenson Button finished second at Marina Bay ahead of Ferrari's Fernando Alonso, whose championship lead was cut from 37 to 29 points with six races to go.

The race was stopped when it reached the two-hour time limit, two laps before its scheduled finish, after the safety car was brought out twice.

"It looks better than before,'' Vettel said.

"It's a tough championship but we are still in it, and looking forward to the next few races, and the goal is to beat Fernando.''

Force India's Paul di Resta finished a career-best fourth ahead of Mercedes' Nico Rosberg. Kimi Raikkonen of Lotus was sixth and maintained third place in the championship standings despite not having won a race. Lotus teammate Romain Grosjean was seventh.

Felipe Massa of Ferrari finished eighth after dropping down to last following a first-lap puncture, and he finished ahead of Australian pair Daniel Ricciardo of Toro Rosso and Mark Webber of Red Bull.

Mercedes' Michael Schumacher retired after a heavy crash into the back of Toro Rosso's Jean-Eric Vergne, bringing the second safety-car period of the night.

Button second

Button was relatively pleased with second place, though disappointed with Hamilton's non-finish, which put a major dent in McLaren's bid to end a 13-year drought in the constructors' championship.

"Seb didn't make any mistakes and we finished second,'' Button said.

"It's good to get some points on the board after the retirement at Monza.

"It's disappointing for the team to have another DNF (did not finish). We can't seem to do it with both cars and for sure that is something we need to work on for the remainder of the season.''

Alonso acknowledged that Ferrari continues to struggle for pace, and his race was one of several which were compromised by the timing of the safety-car interventions, but he was happy with maintaining a good buffer atop the standings.

"It's a fantastic result in terms of points,'' Alonso said.

"It's a positive weekend, a very good weekend; of the four, five contenders we lost points to one and with the others we increased our advantage.''