Nitto ATP Finals 2019: Breaking down Stefanos Tsitsipas's win over Dominic Thiem 

Only a couple of days ago, Stefanos Tsitsipas stood with his arms on his head, having let his racket drop to the court in sheer disbelief as he realized he had ousted Roger Federer and booked himself a spot in the final of ATP Finals 2019. There were a lot of things that were surreal about that moment when the 21-year-old Greek stood shocked as he tried to grasp the gravity of the win while the 38-year-old Roger exited from his 16th semifinal at the prestigious year-ending championships.

It has been a dream week for the spirited youngster as on his debut appearance at the tournament, Tsitsipas went ahead and became the second NextGen player after Alexander Zverev to conquer the ATP Finals.

Stefanos Tsitsipas (left) and Dominic Thiem

Sunday's big final, if anything at all, was a treat for the eyes with both Tsitsipas and the revamped version of Dominic Thiem, fighting tooth and nail for a maiden ATP Finals trophy. Tsitsipas created history and crowned himself the 'King of London' by defeating Thiem in 6-7(6), 6-2, 7-6(4). Having won the Next Gen ATP Finals in 2018, Tsitsipas made it to the big circuit and left everybody spellbound.

In a match that spanned over two hours and thirty-five minutes, Tsitsipas showed wonderful energy that is typical of his young age and a great fighting spirit as he fought back from a set down to win the year-ending championships.

By winning the ATP Finals trophy in London, Tsitsipas has successfully won the biggest title of his career so far and looks alarmingly ready to give some competition to the Big Three in Grand Slams. The 21-year-old long-haired, lanky boy from Athens has also become the youngest player, since Lleyton Hewitt in 2002 (he was 20), to lift the ATP Finals trophy.

The turning point of the match definitely came in the second set when Tsitsipas shifted into Greek God mode and raised his level in the match. It was amazing to see that he never let tiredness creep in despite playing at the highest level for three days in a row.

Even if his body was heavily taxed due to his previous two matches with Roger Federer and Rafael Nadal, it was nowhere to be seen. Although Tsitsipas fought an epic battle with the World No. 1 in his last round robin stage match, the Spaniard got his way in three sets, which remained the only loss the young Greek suffered all week.

Tsitsipas (left) after making it to the final on his debut outing

This whole week had been a dream-like affair for Tsitsipas who had come to the Nitto ATP Finals for the first time in 2016 as a hitting partner for the top 8 players. Back then, he would hit with Dominic Thiem too and neither of them imagined to be playing the final just three years later.

Tsitsipas added his latest trophy to an already impressive 2019 list which consists of titles in Open 13 Provence (Marseille) and Millennium Estoril Open apart from runner-up finishes in Dubai Duty Free Championships, Mutua Madrid Open and China Open.

Having saved 11 out of the 12 break points he faced against Federer in the semifinals, Tsitsipas bought that same gutsy tennis with him in the Sunday final. There were tiring and long rallies and Thiem constantly attacked but the Greek refused to budge even when he faced a break point.

The first-set tie-break may have sided with the Nicolas Massu-coached player but soon enough, Tsitsipas attacked Thiem and broke him in the first game of the second set. It all went the Greek's way after that until the Austrian finally sat up and took notice of his advances after going down an early break in the decider. Thiem broke back and a tense set continued before it headed to a nail-biting tie-break, which finally saw Tsitsipas lifting the trophy on his first try.

Often compared to Federer because of the one-handed backhand he possesses as a weapon, Tsitsipas looks like he is here to stay. He has shown incredible promise over this season with a 54-25 W/L record to end the year. The year-ending championships often acts as a marker for the year to come and with the second year running of NextGen champions, we are in for a new trend and stiffer competition, all aiming to topple the Big Three. For now, it is the Greek general who leads the charge from the front.