NICK HOWSON AT THE KIA OVAL: What changes might we see for the Old Trafford Test and as England flogged their seamers, where was Craig Overton?
We might be in the vaccine age but the sport was given an untimely tremor on the fourth morning with the news of Ravi Shastri's positive Covid-19 lateral flow test which forced three members of the India coaching team into isolation.
Both sides are being kept apart during this series, only coming together during play, which feels like a very shrewd decision rather than combining the bubbles.
It is dramatic to state that one positive could threaten the entire series. But the reality is we don't know what even a small outbreak might do. And, for the health of the individuals as much as anything, we don't want to find out.
A positive case in the Hampshire squad ahead of their Championship match at Warwickshire, fortunately, didn't have a knock-on effect but it could quite easily have done so.
Full stadia and great atmospheres have given the impression that the virus has been kicked firmly into the long grass. Sunday confirmed that it continues to linger menacingly, ready to pull the carpet from underneath our feet.
Head coach Ravi Shastri could miss the rest of the series
"Rahane looks like a player that has 'gone'. It is full and straight - that is a mind that is not quite with it."
It has been a brutal, relentless series. And there is still one Test to go. Changes are inevitable, some of them enforced due to injury or jadedness, others because of lack of form.
Ajinkya Rahane is among the most vulnerable, on either side, to being dispensed with.
The 33-year-old is by far and away the worst-performing of the batters. Jasprit Bumrah is currently averaging better than his 15.57. Though his total haul (109) is short of Shardul Thakur, who's only played two innings.
What is striking is what a struggle this series has been for him, an extension of some poor form that also occurred at home against England in February and March.
His eight-ball ordeal on day four was his nadir, leading to the criticism from Michael Vaughan which began this section.
Rahane has been dropped down the order behind Jadeja, presumably partly as a tactical move but also to give him some additional protection.
It hasn't yet worked and now feels like a way of keeping him in the side, which could be an indicator of what is to come.
Chris Woakes had him on toast. Alex Wharf gave him out third ball to one which was just going over the top. Not for the first time in this series, DRS came to his rescue.
Will Kohli pull the trigger on Rahane?
That ball coming across him is a perennial problem and in Woakes' next over it rung true as he was whacked on the pads and the technology couldn't save him.
It continued a concerning run for Rahane. In his 20 innings since that century at Melbourne, he's scored two fifties, a 49 and 16 scores of 27 or less. Seven single-figure scores, two ducks.
But it is perhaps the manner of his downfalls, being unable to find a way to see off pressure or rotate the strike effectively, which is the most concerning aspect.
The balance Kohli must strike is whether to replace a close confidant, his vice-captain and who led the team to victory in Australia, or plug the gap in the batting. Demoting Rahane down the order for this Test suggests he may well continue to be accommodated, but it isn't as if there are not options among the huge travelling party.
The alternative is to bring in some who has spent the summer watching from afar.
Hanuma Vihari had a three-match spell with Warwickshire in the LV=Insurance County Championship but averaged just 16.66 with one fifty in six innings. Mayank Agarwal, sidelined since suffering a pre-series concussion and Prithvi Shaw are also in reserve, but that might require an unwanted reshuffle.
Suryakumar Yadav has thrilled against the white-ball but without a Test to his name, do you gamble on throwing him into a clutch series decider? And then there is Ravichandran Ashwin and the tantalising possibility of fielding two spinners. We've been over this.
If anyone has seen Craig Overton, please inform the nearest steward.
While Woakes, Ollie Robinson and James Anderson ground away, bowling in excess of 30 overs each in the second innings, the Somerset quick has been missing in action.
He bowled six overs across the first two sessions as India went from a strong position to a dominant one. Anderson was given 10, Woakes and Robinson 11. Overton's contribution extended to two smart slip catches and two-thirds of a day in the sun, before he was given a cameo after tea.
This modest role comes after he was asked to bowl short to a heavy leg-side field on day three.
This particular point isn't about whether the 27-year-old should be in the team, but more about how he's been used. Does Joe Root trust him when the going gets tough? If the answer is no then he surely unselectable in Manchester and beyond.
It is an ominous sign ahead of the fifth Test when rotation is guaranteed. Anderson and Robinson have bowled more than 160 overs each in the series are must be close to breaking point, while Woakes will need to learn to sleep in an ice bath after his biggest workload for a year. There are only four days between the end of this Test and the start of the next.
Speaking of piecing together the England attack, Anderson's workload has been quite absurd. He's only collected two wickets in the second innings of Tests during this series and he's struggled to find a second wind.
The 163.3 overs he's bowled in four Tests is the most he's delivered in a home series since India were last here in 2018. Given he missed almost all of the Ashes and we've had a pandemic, perhaps that isn't a surprise.
But in only two four-Test series on home soil has Anderson bowled more deliveries, and they were 13 and 10 years ago. Anderson is 39.
Craig Overton rues another missed opportunity
Day five of this fourth Test has sold out with some time to spare, meaning 27,000 will be packed into the home of Surrey for the conclusion to this intriguing and fascinating match.
Those who had gambled in the advanced sale would have been shuffling nervously in their seat after 13 wickets fell on day one. But their belief has been rewarded.
Only around 2,000 tickets remained when the game got underway so in many ways it isn't a surprise we have a sell-out. This is the final day of Test cricket in London for another year.
They will assemble with (nearly) all four results on the line.
The most likely outcome is that India storm into a 2-1 lead. They've taken 10 wickets to win a Test in England on four occasions, once on each of the last three tours including on their last visit to the capital.
That said, it will likely be a big day for Ravindra Jadeja, the front-line spin option. For all the talk about who India have not selected, let's speak about the one they have.
His record in England is rather woeful. In 10 matches, his 21 wickets have come at 46. If he isn't dismissing batters, then keeping a lid on the runs and ensuring the strike isn't easily rotated will be the bare minimum. On the fourth evening, there were too many loose deliveries and not enough that tested England. If that doesn't change, then the likes of Jasprit Bumrah, Mohammed Siraj and Umesh Yadav are in for a long day.
The Kia Oval will be packed again for day five
England's task is a mighty one. The 368 would be their biggest total to win a Test the second-highest by any nation on these shores. There have only been nine bigger in history.
On only six occasions have they made more runs in the fourth innings of a Test. And the only time it didn't end in defeat was in 2007 when they made 369 for 6. Against India. At The Oval.
You never know.
Any successful chase will surely require a three-figure score. Only a dozen Englishpersons have Test hundreds in winning causes batting last. You know the last one.
Forty-eight have fourth-innings centuries, but just one sit in the current 11. Moeen Ali's unbeaten 108 against Sri Lanka at Headingley in 2014 is a positive given he is due to come in at No.7, but it highlights the lack of pedigree of the current top six.
It has been frightfully difficult to assess this match across the four days, partly because this pitch has offered something to both teams throughout. Day five promises to finally provide some answers.
Welcome to www.thecricketer.com - the online home of the world’s oldest cricket magazine. Breaking news, interviews, opinion and cricket goodness from every corner of our beautiful sport, from village green to national arena.