Fernando Alonso's imminent retirement from Formula One is a real possibility, world champion Lewis Hamilton said, adding that he hoped the Spaniard would decide to carry on. Former double champion Alonso produced one of the surprises in Sunday's Belgian Grand Prix by jumping from 22nd on the grid to finish seventh but on the whole has endured another miserable campaign since returning to McLaren. In an interview with Spanish newspaper AS published Monday, Hamilton called Alonso "one of the best drivers of all time" but admitted his former teammate could quit the sport. Asked if the Spaniard retiring was a "real possibility," Hamilton said: "Of course it is. He's 35 and he's already earned enough money. He has won enough races, he has enough experience and he doesn't need Formula One to be someone anymore." Nevertheless, Hamilton said he hoped the Spaniard would go on. His contract with McLaren expires at the end of the 2017 campaign. "If he quit next year and I couldn't race against him again, that would be a shame, a real shame," Hamilton said. "It wouldn't be good for this sport and it would send out the wrong message. Formula One would not be the same if Alonso didn't continue. "I still think he is one of the best drivers around, I've always said that," added Hamilton, who is bidding to win a third consecutive world title this season to add to his first triumph in 2008. "I really hope McLaren can make him a car that would allow him to win again, and so I can compete against him again." Alonso is 11th in the drivers' standings on 30 points, 202 behind current leader Hamilton and has not achieved a podium finish since 2014. He had a serious crash in the Australian Grand Prix in March. Alonso has previously brushed off suggestions that he could retire and in April reacted angrily to Sky Sports Formula One pundit Johnny Herbert telling him he should quit. Last Thursday in Spa, however, the Spaniard floated the idea of ending his 15-year career in the sport next year due to recent changes in the sport's regulations. "I think if the cars are fun to drive, I will probably stay longer and drive more years in Formula One, and if the cars are still giving me the feeling that I have in the last couple of years probably I will stop," Alonso said.