The Russian took out his frustration on his shoe as he went 2-1 in round-robin action. (AP)

Andrey Rublev is one of the few "veterans" in the Milan draw. The 21-year-old was a finalist at last year's inaugural Next Gen ATP Finals. But this time around, his patience is being severely tested.

The world No. 68 needed five sets (albeit abbreviated ones) to get past Taylor Fritz in his opening round on Tuesday. 

The Russian then suffered a four-set loss to a red-hot Alex de Minaur, where he got a little frustrated, to say the very least. 

The shoe survived the onslaught as Rublev bounced back on Thursday to dismiss local wild card Liam Caruana.

Caruana has been fighting a losing battle all week as he's ranked just outside the Top 600, while the rest of the field is made up of Top-100 players. In three matches, the 20-year-old Italian won just one set, off of Fritz.

Still, he has had moments of brilliance:

Despite now playing the event twice, Rublev is vocally not a big supporter of the innovative rules in Milan. 

"Like I said always that I'm not a big fan of these rules. I think it's a little bit not fair because, in the end, everything make no sense," Rublev said about the short scoring sets. "Even if you play so you don't feel nothing today and the other guy is playing so good, you still can win the match, which is not happening normally when you play the real match."

Rublev is now playing a waiting game to see if he will advance to the semifinals, as it depends on how the Thursday night match between De Minaur and Fritz pans out.

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