Seven Tests, 24 wickets, an average of 30.16. That was R Ashwin's record during India's run of overseas tours last year.

How good are those numbers? Well, that average is the best among those of the eight spinners with ten or more wickets in South Africa, England and Australia since the start of 2016. In that time, Nathan Lyon has averaged 36.71 in these three countries, Moeen Ali and Rangana Herath in the 40s, and Yasir Shah 56.03. Ashwin's economy rate of 2.38 is the best on that list too.

Those numbers reflected the role Ashwin ended up playing on those tours. Through his career, Ashwin has been known for his strike rate - which remains the best among all spinners with more than 200 Test wickets - but India's strike bowlers on those tours were their quicks. Ashwin, for one reason or another, ended up playing a holding role.

Think back to Adelaide, where he conceded only 149 runs in 86.5 overs - nearly a full day's Test cricket - across the Test match, and picked up three wickets in each innings, but without getting ball after ball to leap out of the rough like Lyon did. Lyon bowled 16.5 overs less than Ashwin, but picked up two more wickets, including six in India's second innings. He also conceded 56 runs more than Ashwin.

How much of Ashwin's bowling style - controlled and probing, but without the ripping turn and bounce that runs through sides - was down to design, and how much of it was down to his physical state?

For any spinner, the amount of purchase they extract is proportionate to the work they put on the ball with their action. You can't put as much body into your action if some part of your body is giving you trouble.

The groin has been Ashwin's problem area for a while. Soon after the 2016-17 home season - in which he bowled more overs than anyone ever has in a single season of Test cricket - he sat out the IPL to recover from sports hernia, a soft-tissue injury in the groin area, which is commonly seen among sportspersons who are required to put their body through repetitive twisting motions.

The problem resurfaced on the England tour last year. Ashwin played despite being less than fully fit in Southampton - where Moeen, getting the ball to jump out of the footmarks in a way Ashwin didn't, was England's match-winner - and missed the next Test at The Oval. After his Adelaide exertions, Ashwin's injury flared up again, and he missed the last three Tests in Australia.

Meanwhile, Ravindra Jadeja came into the side, and ensured Ashwin wasn't missed too much. He took seven wickets at The Oval, and five in a victory at the MCG. He also scored eighties at The Oval and the SCG. In Sydney, India played two spinners, and Kuldeep Yadav picked up a first-innings five-for.

We can't be sure how much of it was down to Kuldeep's impressive bowling on a flat pitch, and how much to his impatience with Ashwin's fitness issues, but India head coach Ravi Shastri, speaking to Cricbuzz after the Australia tour, asserted that Kuldeep had become India's "number one spinner in overseas Test cricket".

By the time the latest West Indies tour rolled around, therefore, Ashwin was in a fight to regain his place. There was room for one spinner in India's combination in Antigua, and India went with Jadeja.

Kuldeep Yadav is cheered by his team-mates after his five-for Getty Images

Kuldeep may have been in contention, but his white-ball form had fallen away somewhat between Sydney and Antigua, and given that this was India's first World Test Championship game, they may have wanted to pick someone with more experience, and perhaps more batting ability too. That left Ashwin and Jadeja.

It couldn't have been an easy decision to leave Ashwin out, given his outstanding career record, his numbers - with ball and bat - against West Indies, and his recent County Championship form for Nottinghamshire, for whom he picked up 23 wickets at 19.91 in three Division One games.

But equally, Jadeja had made himself extremely difficult to drop. Since the start of the 2016-17 home season, his record with the ball has been neck-and-neck with Ashwin's, while his batting returns have been significantly superior. In that time, he has been the world's best allrounder in terms of difference between batting and bowling averages.

In the end, Jadeja made a key contribution to India's win in Antigua, scoring 58 and turning 189 for 6 into a first-innings total of 297. His bowling was less successful, with his two first-innings wickets coming either side of some stick from Darren Bravo, Roston Chase and Shimron Hetmyer - who scored a combined 46 off 55 balls against him - and his four second-innings overs going for 42 runs with Kemar Roach hitting three sixes off him.

Spinners can sometimes end up with figures like that even when they have bowled well, and India won't be unduly alarmed by Jadeja's display in Antigua, especially when their quicks were so good. Now, unless India play two spinners - and perhaps even if they do - Ashwin will quite likely sit out the second Test in Jamaica too.

It's not an entirely unfamiliar situation for Ashwin - Jadeja briefly usurped him as the No. 1 overseas spinner back in 2013-14, and Karn Sharma played ahead of him in the 2014 Adelaide Test - but it will still irk him, given his status as one of India's greatest match-winners, and given that so much of his recent struggle has come about thanks to factors not in his control. It can't be easy to accept the Stuart MacGill role when you've been Shane Warne for so long.

That said, the Ashwin-Jadeja dynamic is now perhaps more like the tussle between Anil Kumble and Harbhajan Singh, which only resolved into a clear-cut hierarchy after the 2003-04 tour of Australia. Harbhajan returned home after aggravating a finger injury in the first Test, following which Kumble came into the side, picked up 24 wickets in the next three Tests, and became India's undisputed No. 1 spinner. What further twists await us in the Ashwin-Jadeja story?