Mumbai, Nov. 18 -- Jannik Sinner slumped on the bright blue court after the final point and lay flat on his back for a good few seconds. The last time he did that was after the final point of the 2024 Australian Open, to become a Grand Slam champion for the first time. In his three major triumphs after that, he simply lifted his arms in celebration. This reaction was not typical of Sinner. This stage too was not the theatre called Grand Slams. What, then, could explain the gush of emotion from an otherwise mild-mannered Italian on winning the season-ending ATP Finals? Sinner, after all, had also gone all the way last year, equally ruthlessly without dropping a set, and in front of his home fans in Turin. Been there, done that. Perhaps it had something to do with the guy he beat in the final. Carloz Alcaraz had Sinner's number in seven of their eight previous clashes before Sunday. In Turin, after a humbling defeat in New York for the US Open title, Sinner pulled one back with a closely-fought 7-6(4), 7-5 victory. This "W" is significant for Sinner not only in the context of this fascinating rivalry between two young stars eclipsing everyone else in men's tennis at the moment, but also on the back of the Italian's words after the US Open. In a refreshingly frank assessment after that four-set final where the Spaniard sparkled with his all-round craft, a gloomy-looking Italian spoke about the need to change things, not be predictable (with his shots) and move out of his comfort zone (of the baseline). This, lest we forget, came from a player who made the final of every Slam this year, won two of them, and spent 65 consecutive weeks as the world No.1. All great things and yet, in his mind, status quo wasn't good enough specifically against the one opponent that pushed him the most. "Now it's going to be on me if I want to make changes or not," Sinner said in New York. A little over two months on, it's evident that he has. And glimpses of that were on show inside the indoor hard courts of Turin. Two things stood out in Sinner's shake-up work: the serve and the variety in play. Two points to highlight the latter: Down 0-2, 30-15 in the second set, Sinner, standing just behind the baseline to Alcaraz's return, dished out a drop shot that even Alcaraz couldn't get to. Then at the break back opportunity at 2-3, Sinner, after shanking the return, came up with a sliced forehand volley drop from well above his shoulder that Alcaraz didn't even bother chasing. To go with his baseline sturdiness, Sinner won 88% (7/8) of the points at the net to Alcaraz's 50% (6/12). "From the back of the court, it's (about) being a bit more unpredictable," Sinner said after the final. "It worked well, or at least better." What worked even better, as both the protagonist and his rival concurred, was the serve. "I felt the improvements of Jannik.especially in the serves," said Alcaraz, who was affected a bit by a hamstring issue mid-match. In the New York final, Alcaraz won 83% points on the first serve to Sinner's 69% and 57% on the second to Sinner's 48%. In the Turin final, the first serve numbers flipped (Sinner won 84% points to Alcaraz's 73%). While on the second, Sinner got better compared to the US Open (54% to Alcaraz's 57%), in terms of efficiency and potency. "Second set I was returning pretty well, but he came out with a 185-190 (kmph) second serve. That surprised me, to be honest," said Alcaraz. Sinner was prepared to be bolder in his first strike at the cost of more errors (5 double faults). Work on changing that mindset, and the motion of the serve, as revealed by Simone Vagnozzi, was done immediately after the US Open by his coaching team of Vagnozzi and Darren Cahill. "It is not just about the first-serve percentage," Cahill told ATP. "If we were really concerned about the first-serve percentage, we would let him slow the serve down to let him get more first serves in. He's actually pumped up the miles per hour, and he is getting the ball closer to the line, which means he gets a lot more free points." Something similar was done by Team Alcaraz in the off-season last year when they tweaked the Spaniard's service motion and movement. Alcaraz served as good as ever at the US Open. That's the thing about these modern-day giants and their classic rivalry - they may be collectively a cut above the rest, but either will spot, accept and get down to work towards erasing the chink almost exclusively with regards to the other. Sinner is already looking forward to a "very important" December for the continued change-in-process work. And Alcaraz is already looking forward to their next battle to strike back. "Hope you're going to be ready for next year," Alcaraz told Sinner on court, "because I will be ready."...