England head into Thursday's fourth Test against a resurgent India at Southampton facing several awkward questions.
Whether Jonny Bairstow is fit to play at all, never mind keep wicket, after suffering a broken finger during India's dominant 203-run win in the third Test at Trent Bridge, has still to be decided.
"The swelling has gone down," Bairstow told reporters in Southampton on Tuesday.
"I'm going to try and keep wicket in training this afternoon as well."
Even if Bairstow is included purely as a specialist batsman, England, seeking a victory that would see them win the series, will still have to consider whether they need to bolster their fallible top order.
- 'Work on a weakness' -
The risk in fielding an injured player was highlighted by India's Mohammed Shami, who said Bairstow would be targeted if he batted at Southampton.
"When you see that a batsman has a weakness and he feels uncomfortable in some way, you'd prefer to work on that aspect," said paceman Shami. "We will definitely look at that."
If Bairstow is ruled out completely, James Vince is set for an England recall on his home ground, with one-day wicket-keeper Jos Buttler taking over behind the stumps as happened during the third Test.
But even if Bairstow plays, the in-form Vince could still return in a bid to strengthen the batting -- England have been 100 for four or worse in half of their past 62 Test innings.
Vince was dropped by England after a tour of Australia and New Zealand that left him with overall Test figures of 548 runs from 13 matches at a low average of 24.90 and a top score of 83.
But this season the Hampshire captain has scored 847 runs at an average of 56.46 in England's first-class County Championship.
That includes innings of 74 and 147 against Nottinghamshire at Southampton last week.
England also have concerns over the balance of their attack, with pace-bowling all-rounders Ben Stokes (knee) and Chris Woakes (thigh) not yet fully fit.
If either man is ruled out, it could lead to a return for 20-year-old Surrey left-arm swing bowler Sam Curran.
England also have to decide whether to recall off-spinning all-rounder Moeen Ali, either as a replacement for, or an extra slow bowler in support of, leg-spinner Adil Rashid.
An innings of 219 and figures of eight for 89 against Yorkshire have put Ali's name back in the frame for a match on a ground where he took six for 67 against India during England's 266-run win in the corresponding Test four years ago.
That same Test also saw Alastair Cook end a run of low scores with an innings of 95 and England would be delighted if their all-time leading Test run-scorer put another bad trot behind him in similar fashion this week.
- Anderson eyes McGrath mark -
Meanwhile, James Anderson is on the verge of becoming the most successful pace bowler in the history of Test cricket.
Anderson has an England-record 557 wickets in Tests and is now just six shy of retired Australia great Glenn McGrath's tally of 563 -- the most taken by any paceman at this level.
"We've been able to learn a great deal from Anderson," said Shami. "So far, what I've learnt from Anderson is this: the stricter and the more accurate you are, the better it is."
India have yet to field the same side for two consecutive Tests under Virat Kohli's captaincy.
But that could change following a dominant display in Nottingham where, for the second match of the series, Kohli scored exactly 200 runs, including a century, having achieved the same feat in the first Test at Edgbaston.
Victory kept alive India's hopes of coming from 2-0 down to win a five-match series, something achieved just once in Test history, by a Don Bradman-inspired Australia against England in 1936/37.