Alonso and Hamilton, then a rookie, did not often see eye to eye during a torrid season together at McLaren [ Images ] in 2007.
The two drivers have long since grown to respect each other and Hamilton is now cheering for Alonso, who won back to-back drivers' titles with Renault [ Images ] in 2005 and 2006.
"I feel like Fernando has deserved it through the year. Ferrari [ Images ] haven't made one mistake. He hasn't always been the fastest but he has been up there," the Daily Express quoted Hamilton, as saying.
"He has driven like the champion he is all year and I feel as though he is a three-times world champion. Red Bull have been more up and down but they have still done a great job," he added.
After Button failed to finish in Korea and Hamilton came in 10th, McLaren have now dropped to third in the constructors' championship, which they have not won for 14 years.
However, they could yet snatch victory if they can end a series of technical failures, the latest being a rear rollbar which gave Hamilton no chance at the weekend.
"While everyone has been working so hard, other teams have worked hard and done a better job. Ferrari have done a great job and Red Bull have done a fantastic job," said Hamilton.
"At some stage in the future, I am sure McLaren will put together a strong package and the drivers here will make the best use of it. This is a fantastic team with a great history and will always be competitive," he added.