The 15th seed performed impressively on a sun-drenched Centre Court, thrilling the crowd with his inspiring tenacity, sharp ground strokes and counter-punching style.
The Australian raced into an early lead against Monfils. The Frenchman crumbled on serve in the eighth game with a wayward backhand allowing Hewitt to seize the initiative and edge 5-3 ahead.
Hewitt, who won Wimbledon in 2002, was supremely effective at the net all afternoon and fittingly secured the opening set with an assured forehand volley which left Monfils sprawling.
Monfils, the 21st seed, found some consistency in the second set. The 23-year-old held his serve throughout, managing to discover a ferocious ace whenever Hewitt threatened to craft a break point.
With both players serving well the set was inevitably decided by a tiebreak. Breaking the pattern of the previous 21 games, nerves started to sweep over both players with double faults swiftly going from rarity to common theme.
Monfils had opportunities to level the match with several set points but lacked composure at the crucial moments. Hewitt cemented his position with a delicate backhand volley on set point.
Lifted by the tiebreak success, Hewitt quickly raced into a 4-1 lead in the final set. Monfils, however, managed to amount a comeback of sorts, aided by some reckless shots by Hewitt which saw the scores level at 4-4.
However HewittÃ¢â‚¬â„¢s fearsome reputation on the ATP tour was once again highlighted as the 29-year-old dug deep to break to love and seal victory on his 101st match on a grass court.
“I knew it was going to be tough,” Hewitt told the BBC. “I’ve the lost the last couple of times to GaÃƒÂ«l, he is a tremendous athlete and has a really big serve.”
“The second-set tie-break was huge, we both had opportunities and I was able to pull through. It could have gone either way in the third,” he added.
Hewitt will now face No.3 seed Novak Djokovic on Monday.
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BIOGRAPHY: Ethan Hazard
BIOGRAPHY: Daniel Sturridge