Matteo Berrettini edged out Gael Monfils 6-4 6-4 3-6 3-6 6-2 to reach his maiden Australian Open semi-final.
The Italian was too strong in the key moments as he outlasted the Frenchman to reach the last four in Melbourne.
Despite a strong start to the season and a vintage comeback, Gael Monfils ran out of energy and produced key errors in big moments.
Berrettini will now face 20-time grand slam champion Rafael Nadal in the semi-finals on Friday.
It was a strong start from both players as they knew it was a golden opportunity to reach the semi-finals of a grand slam.
However it was Berrettini who drew first blood with some aggressive groundstrokes mixed with shortening the points at the net.
A break to love secured a 3-2 lead and the Italian had a pretty comfortable set on serve with some big first serve and forehand combinations.
Monfils had a better read on the serve in the second set, creating a break point when the Italian served for the set.
But the power of Berrettini counter-attacked the insane defence of the Frenchman as he closed out the opening set in 37 minutes.
In the early exchanges of the second set both players had to endure tough tests on their serve with Monfils saving three break points for an opening service hold.
In the fourth game Berrettini overcame a 15 minute hold of serve as he saved three break points and sealed a crucial hold for 2-2.
This seemed to be the turning point as he then turned up the aggression on both wings and a clinical seventh game secured the break for a 4-3 lead.
The Italian comfortably secured the second set with a hold to love as a two set to love lead was obtained and surely a comfortable straight sets win.
But this was Gael Monfils we are talking about and nothing is straightforward against the Frenchman with the third set showing why.
Monfils, one of the biggest fighters in tennis, continued to work the angles against a now passive Matteo Berrettini.
Eventually extending the rallies and making the Italian cover a lot of the court worked as the Frenchman secured the break for a 4-2 lead.
Monfils executed effected patterns of play on serve as he wrapped up the third set and rallied the crowd in his favour.
Berrettini’s legs were suddenly looked tired as well as his mental concentration going as sublime Monfils winner on the line saw him break for a 3-2 lead as Berrettini seemed to think the shot was out.
A re-energized Frenchman built his lead from then as Monfils took command of the rallies and dictated the tempo of the match.
Berrettini’s passive play wasn’t getting through Monfils’ angles and effortless power as another long game went the way of the Frenchman as he secured a second break to level the match at two sets all.
Now the pressure was on the Frenchman as the crowd were gearing up for an entertaining final set.
But this time it was Monfils’ passive play and fatigue that played a part in the final set as Berrettini found his consistent power when he needed it most.
A quick double break was secured for a fired up Berrettini who booked his place into the semi-finals in Melbourne for the first time.
