Root will urge Jennings to enjoy Test arena if he makes England bow in Mumbai

After Haseeb Hameed's mid-tour departure with a badly-broken left hand, Jennings appears to be in line to become captain Alastair Cook's 11th opening partner since the retirement of Andrew Strauss four years ago.

The Durham left-hander, set to join the squad alongside fellow replacement Liam Dawson - who will fill the vacancy left by injured spinner Zafar Ansari - is the most obvious contender to open the batting in the fourth Test in Mumbai.

Root had to do the job in the second innings of England's eight-wicket defeat in Mohali, moving back up to the top of the order for the first time since the 2013 Ashes.

He is expected to return to number three, but will be an obvious source of useful information for Jennings on several counts - having played his own first Test at Nagpur, in the middle order, in the final match of England's last series in India in 2012.

From his own experience, Root believes there is no way anyone can avoid inevitable nerves - but harnessing them into a sense of enjoyment and excitement worked for him, when he began his Test career with a half-century at his first attempt in a series-sealing draw.

Asked what wisdom he can impart to Jennings, Root said: "More than anything, you are naturally going to be quite nervous, so I'll try not to say all that stuff about not being nervous and trying to relax.

"Just enjoy it. You've got an opportunity to play for England in Test cricket - try to soak up the whole occasion and make the most of it.

"Try not to get too caught up in things that could happen, and just enjoy being in that moment and putting on the cap and the shirt.

"Just be proud of that achievement, and see where it takes you."

Root has played only a handful of times against Jennings - including in last summer's NatWest T20 Blast semi-final at Edgbaston, where Durham beat Yorkshire only to then lose to champions Northamptonshire despite 88 from the opener.

A very different challenge will await if he does make his Test debut at the Wankhede Stadium, as England try to kickstart a comeback from 2-0 down in pursuit of an unlikely series draw.

Root has seen and heard enough about the 24-year-old, after his prolific breakthrough summer, to be confident he can rise to the occasion.

Some of the information has come via charismatic England and Durham match-winner Ben Stokes - although it sounds as if Root will be careful not to read too much into some details from that particular source.

"What you get from Stokesy isn't always very trustworthy," he said, with a smile.

"But he's obviously had a very good season, good couple of seasons actually across all formats.

"I think he's deserved his opportunity, and I hope if he does play he takes his chance - and proves that he can put those performances in county cricket into Test cricket.

"I've seen him play a little bit, more in white-ball cricket. But he's got a very solid technique, looks very organised and obviously knows what he's doing."

Dawson too may be given a debut next week, if England decide they need three spinners at a venue where Monty Panesar and Graeme Swann took 19 of the 20 wickets in a famous victory four years ago.

The Hampshire all-rounder has already won his first cap in each of the limited-overs formats, and made a fine impression especially on England coach Trevor Bayliss - who has often spoken in glowing terms about him.

Root added: "One thing he's got is he's a real competitor.

"When he gets out on the field you can see his desire to do well, to try to affect the game.

"He's a great lad, good fun to work and play with.

"If he gets an opportunity to play Test cricket for England, I'm sure he'll be desperate to do well."

The majority of England's squad will fly to Dubai on Thursday, for a short mid-series break, before re-convening in Mumbai early next week.

When they do so, updates on Stuart Broad's foot injury and Chris Woakes' thumb issue will be high on the agenda - along with fine-tuning selection for a must-win match.

  Joe Root, pictured, will be happy to give Keaton Jennings the benefit of his experience in Mumbai
Joe Root, pictured, will be happy to give Keaton Jennings the benefit of his experience in Mumbai