The world No. 136 upset Jack Sock and then beat fellow lucky loser Ruben Bemelmans. (Getty)

Who is Jurgen Zopp? The Estonian is a lucky loser at Roland Garros that has found himself in the third round. 

The 30-year-old was one of eight men benefitting from the new first-round retirement rule at Grand Slams, which fines players up to their first-round prize money amount ($49,240 in Paris) if they retire or don't put in their best effort. Zopp had lost in the final round of qualifying to Denis Kudla, 6-2, 6-1.

Going into his first-round match against No. 14 seed Jack Sock, Zopp had just nine ATP-level wins under his belt. Despite that, and despite going down 1-4 in the fourth-set tiebreak, Zopp prevailed, 6-7 (4), 6-2, 4-6, 7-6 (5), 6-3.

The match had its fair share of drama, and the world No. 136-ranked Zopp celebrated like he had won Roland Garros. 

He then went on to win the battle of the lucky losers over Ruben Bemelmans, again in a thrilling five-setter, 4-6, 3-6, 6-3, 6-4, 6-4. Zopp is the first Estonian player to reach the third round of a Grand Slam. 

While Zopp may be new to Grand Slam success he has won 14 ITF Futures titles and three ATP Challenger crowns during his career. He reached his career-high ranking of No. 71 in 2012. With his run so far this week, Zopp earns $152,000, eclipsing his 2018 prize money total of $33,000 going into Paris. 

Zopp has a reasonable shot of doing even better when he faces No. 70-ranked Maximilian Marterer for a spot in the round of 16. 

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