England coach Trevor Bayliss has challenged Joe Root to carry on improving in his role as a captain after guiding England to a momentous series victory away to Sri Lanka.

Root has been in charge of the Test team for 18 months but this series victory, England's first away from home for three years, and the manner in which it has been achieved has been a significant step forward for both the team and the 27 year-old's captaincy. If some had begun to wonder if Root was cut out for the top job after last winter's Ashes humbling and a year of limited progress, the victories over India during the summer and now in Sri Lanka have pushed those questions to the margins.

Bayliss, however, believes that Root still has scope for improvement despite the Test team's recent strides under his leadership. "I still think he'll improve even more from where he's at at the moment," England's coach said. "Like any young captain, he'd probably like to do a few things differently but the more you have these types of wins in these conditions that just gives the captain confidence and the players confidence in the captain that he can make the right call. He'll just get better and better."

Root confessed to second guessing himself at times during England's victory in the second Test at Palekelle. He admitted he could have handled the two elongated sessions on day four better when Sri Lanka reached tea with five wickets remaining and just 80 runs needed for victory. "I didn't manage those as well as I could as captain, having not had that experience before...it's a good learner for me," he said after play on day four.

Root also admitted to wondering whether he got it wrong when opting not to use the reverse swing of Ben Stokes on the penultimate day when England were struggling to make the necessary breakthrough. Given captains make hundreds of decisions each day of a Test, it is natural for them to question the choices they make but Root's positive leadership in Sri Lanka, epitomised by his fine hundred in the second innings in Palekelle, has been a key reason for their series victory. He's not yet the finished article as a leader but he is certainly getting there.

Given Root's lack of captaincy experience, he was always going to need time to adjust to the role tactically but perhaps the most pertinent questions being asked of his captaincy after last winter's Ashes series were those about whether England were yet a team modelled in his own image. Was the team playing the way he wanted them to? Was the influence of senior players too strong? Was his message getting across?

That is difficult to know but on the evidence of the last six months, this England team has certainly improved. Alastair Cook's retirement, and the introduction of a number of new players who have put the likes of Stuart Broad and Jonny Bairstow under pressure, has breathed new life into the team. There hasn't been a changing of the guard per se, but there has certainly been an injection of energy and intent, mirroring the attitude of the one-day side under Eoin Morgan.

"Off field it's starting to get there," Bayliss said of the atmosphere within the Test squad in comparison to the white-ball set-up. "Obviously there's a few more guys in that one-day team in the Test team with [Adil] Rashid and [Jos] Buttler but it's starting to feel a good-feel just like that one-day team."

The likes of Ben Foakes, Rory Burns and Jack Leach have added much in Sri Lanka just as Sam Curran did against India in the summer. These players have bought into the message Root and Bayliss have been preaching. "The whole time we've spoken about being positive and playing your own game in that positive manner," Bayliss said. "For example, I thought Keaton Jennings and Foakes down in Galle - their innings were fantastically positive. They played in their fashion in a positive manner.

"Look, we've always been about having that positive intent. Joe himself has probably taken that to another level but it doesn't necessarily mean guys like Foakes, Keaton Jennings and Burns have to go and play like Joe Root. It means going out and playing in a positive Keaton Jennings way for example and I think we've done that pretty well over here."

England will hope to continue their good run of form in the final Test in Colombo. Bayliss said they would look at the pitch before deciding whether there would be any changes to the eleven but suggested there would be no thoughts of rotation. If Curran recovers from the side strain he suffered in Palekelle, that would mean Bairstow and Broad, two of England's senior players, missing out yet again.

Despite their frustration, Bayliss says the attitude of the pair has been spot on. "One of the great things that hasn't been spoken about over the last two games is Stuart Broad missing out and Jonny Bairstow but the way they've taken it has been absolutely fantastic. It makes the feeling around the squad so much better. They are very much part of a squad and they realise that. They realise we're picking what we think is the best one to win each match and they've taken that on the chin - it's been great."