Jack Sock keeps his eyes on the prize.

The high level of anticipation for this encounter was met by the riveting action that was on offer in London this evening. World number nine, Jack Sock, overcame world number three, Alexander Zverev, in a tightly contested affair. The fiery American employed his entire arsenal with aplomb as he dispatched the young German in three sets.

Each player came into the match with a win and a loss on their ledger for the tourney. Similarly, their head-to-head record stood at one, apiece. By virtue of their respective wins against Cilic and losses to Federer, they were deadlocked in the standings. With the hard-fought win, the 25-year-old advances to the semifinals of Group Boris Becker, where he will square off with Bulgarian, Grigor Dimitrov. Citing momentum and form, many pundits did favor the American going into the contest. Ever eager to please, the 25-year-old Sock put some of his athleticism on display early with his mongoose-like reactions at the net.

Both athletes were more than game, and we are witnessing some stellar growth from both men. Their games are maturing by leaps and bounds, right before our eyes. Behind a devastating serve, and a solid all-court game, “Sascha,” as his fans call him, made a strong statement by finishing second in his group in his maiden appearance at the ATP’s season-capping event. The wheels on the 6’6” German are impressive, and his footspeed enabled him to make some tough pick-ups. Sock, however, managed to save two early break points, in his opening service game. He struck first with a break in the seventh game, courtesy of some extremely slick and cagey court sense. At the very least, we are being treated to some dramatically visible advances in play from this tournament’s participants.

Following a hard-fought Zverev hold, opportunity presented itself for Jack Sock. After saving six break points on his own serve, he served for the first set. Putting the vaunted forehand on display, as well as some exquisite touch, he tucked it away with relative ease.

After hanging tough to hold his serve once more, Zverev staked out an early lead in set number two. He then backed that up with a break to 15, and punctuated the effort with a loud roar and fist pump. Another hold, and it was clear that the German was finding his range. Not a moment too soon, as he had significant ground to make up. A double break promptly followed, as Sock’s discipline went down the drain. Blink and you could’ve missed the next game. Sock had mentally conceded the set at that point, and Zverev was sprinting unhindered. He managed a hold for pride, and an anticlimactic final hold from ensued. The breadstick was baked, removed from the oven, and placed on glorious, steaming display. Spectators would get their wish: more tennis.

A single set to decide the victor, and Sock would serve first. An extended rally at deuce went the way of the German, however, and the early break soon followed, courtesy of repeated impossible gets at the baseline, defending like his life depended on it. A “salty” Sock fired a ball into the crowd for a second time in the match, earning himself a point penalty. Nevertheless, two double faults promptly gifted the break straight back to the American. Bad time for a clunker. Sock showed some fire of his own, backing up the break with a speedy hold, punctuated by a savage roar. Zverev’s serve abandoned him at the worst time. Yet another double fault gave his opponent the critical break advantage. A strong service hold to consolidate his lead was just what the doctor ordered, and the finish line drew tantalizingly close. A hold for Zverev brought him within shouting distance. Fatigue appeared to be his nemesis, as the fitness battle seemed to favoring his bearded foe. An unexpected break soon followed, and things were right back on serve.

Routine hold, three games on the trot, and Zverev found himself on level terms. By this point, the match had taken on a completely unpredictable tenor. Sock with a dazzling display of one-two combinations held with ease, and was now a game away from the match. The tension was palpable. Zverev’s eight double fault put him on the precipice, as it brought up match point. With a lazy wide stroke, Sock had secured victory.

The American number one advances, then, to the “Final Four,” joining Federer and Dimitrov. He is through, by a score of 6-4, 1-6, 6-4, in 1:53. The winner of Thiem versus Goffin will join them. Zverev, meanwhile, bids adieu to his 2017 season. Nothing to cry about for him, as it’s been a breakthrough campaign with a very strong finish.

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