Beckham celebrates Donovan's penalty against Houston
England midfielder David Beckham helped his Los Angeles Galaxy side move a step nearer the Major League Soccer title with a 2-0 victory over Houston Dynamo.
Beckham's extra-time free-kick was poked home by Greg Berhalter before Landon Donovan sealed the semi-final series decider from the penalty spot.
The Galaxy also overcame two floodlight failures and face Chicago Fire or Real Salt Lake in next week's Seattle final.
It will be Beckham's last MLS game before rejoining AC Milan on loan.
The Galaxy's Western Conference Championship clash against two-time MLS champions Houston was halted for more than 30 minutes as the south of Los Angeles was twice plunged into darkness by a power cut.
The first stoppage came in the 18th minute when the floodlights at the Home Depot Centre failed, with the Carson neighbourhood completely blacked out.
The players were kept on the pitch by referee Terry Vaughan during the delay but play did not resume for another 18 minutes.
We've got a great bunch of guys that are working hard for each other and it's been tough, so we're happy
Los Angeles Galaxy midfielder David Beckham
Beckham, who will return to Italy in January, had the first clear-cut chance after the resumption, whipping in a curling free-kick from 25 yards that was turned round his post by Houston keeper Pat Onstad.
Donovan saw a 20-yard strike saved a minute into the second half before Houston's Andrew Hainault was denied two minutes later.
A second power failure then followed, halting play for a further 16 minutes, although neither side was able to make a breakthrough in normal time.
It finally came in the 104th minute, however, when Beckham's free-kick to the back post was headed down by Omar Gonzalez and fellow defender Berhalter steered the ball past Onstad.
Houston's agony was compounded four minutes later when substitute Alan Gordon was felled in the area by Ricardo Clark and Donovan converted the resultant spot-kick.
Beckham nearly made it 3-0 with a trademark 30-yard free-kick that just curled past Onstad's top right-hand corner but by then the Galaxy were home and dry.
Afterwards Beckham praised his team-mates and Tim Leiweke, president and chief executive of Galaxy owners AEG, for putting the MLS team within reach of their first title since 2005.
"It's so important for us to do well, we've had so many disappointments over the last four years and Tim Leiweke and everybody have put so much behind this team," said Beckham.
"This club and this franchise and the players are doing them proud.
"We've got a great bunch of guys that are working hard for each other and it's been tough, so we're happy."
Galaxy had confirmed themselves as Western Conference winners with a 2-0 win over San Jose Earthquakes in October.
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