Portimao (Portugal), May 3 (IANS): Mercedes Formula One driver Lewis Hamilton said that the hard-fought win in the Portuguese Grand Prix had left him physically and mentally drained.

The British racer delivered a bold pass on Mercedes team-mate Valtteri Bottas and drove off into the Portimao sun to win the race on Sunday and increase his lead in the Formula One world title standings, DPA reported.

"That was such a tough race, physically and mentally, keeping everything together," said Hamilton.

Hamilton started second but had to regain a spot lost to Red Bull's Max Verstappen and secured victory by sweeping round pole sitter Bottas on the 20th lap of 66 around the 4.684km Autodromo Internacional do Algarve.

Verstappen then struggled behind Bottas until he overtook the Finn straight after mid-race pit stops but Hamilton had already built a gap substantial enough to earn a second season win from three races and the 97th of his career.

Hamilton now leads the championship on 69 points with Verstappen, who secured the fastest lap bonus point, on 62 going into the Spanish Grand Prix on May 9.

"With Valtteri (Bottas), I had to make the move early on before the tyres were destroyed and I just managed to get him at Turn One," the champion, describing the bold pass, said.

As Verstappen was held up by Bottas, Hamilton produced a series of fastest laps and though he emerged from his lap 38 pit stop behind the Red Bull of Sergio Perez -- who drove a massive 51-lap first stint -- he was comfortable in the effective lead.