Nurture Adil Rashid's confidence in Sri Lanka, Shane Warne tells England

Warne hopes England stick with Rashid (2:01)

Former Australia bowler Shane Warne explains why England should stand by their own legspinner in Adil Rashid (2:01)

Shane Warne says that he is expecting "big things" from Adil Rashid in the Test series in Sri Lanka, but has called on Joe Root to show more faith in his legspinner to ensure his confidence stays high.

Rashid came through a peculiar summer with his reputation enhanced thanks to an important, if bit-part, role against India. He bowled just 87 overs across the five Tests - Moeen Ali, by contrast, got through 76 in just two appearances at the Ageas Bowl and The Oval - but picked up 10 key wickets, the most in a home series by any English legspinner since Tommy Greenhough in 1959.

Warne, however, believes that England have to capitalise on that promising return if they are to get the best out of a player who wasn't even available for Test cricket at the start of the summer, having signed a white-ball-only contract with Yorkshire.

"It's very important that the captain backs you," Warne told ESPNcricinfo at a Laureus event at The Oval. "Early on in the series, Joe Root needs to throw the ball to Rashid. Bowl him first change, or even open the bowling with him if the conditions suit in the second innings. Let him know he's the No.1 spinner and that he's got all the support of the captain. That is crucial."

Warne himself enjoyed his breakthrough moment on Australia's tour of Sri Lanka back in 1992, when he was trusted by his captain Allan Border in the key moment of a tense first Test in Colombo. He responded with three quick wickets to salvage a 16-run victory, and didn't look back thereafter.

"All I know is that, as a young legspinner, it was so important to have a captain who would back me no matter what, even when it doesn't go well. You just know when you've got the support of your captain, and when you are an afterthought."

For much of the India series it was hard to gauge quite how much faith Root had in Rashid. He didn't bowl at all during the second Test at Lord's, and went wicketless at the Ageas Bowl while his spin partner Moeen Ali claimed nine. But come a tense final Test at The Oval, Rashid produced his most memorable moment - a massive legbreak to India's centurion KL Rahul. The ball burst out of the rough outside the right-hander's leg stump to hit the top of off and end, at a stroke, any remote possibility of India chasing down a massive victory target of 464.

The delivery evoked comparisons with some of Warne's most memorable deliveries, in particular his ripper to Andrew Strauss at Edgbaston in the 2005 Ashes, but Warne himself insisted that Rashid deserved to be judged on his contribution to the series as a whole.

"I don't think one ball justified the whole selection," he said. "It's about what impact you have through the series. Does the captain have confidence to bowl you when it's tough, or when the conditions suit, or as a change-up when nothing's happening? Because a legspinner makes something happen. Even when he doesn't bowl well, he can still make something happen. I hope they stick with him because all his wickets were invaluable through the series."

There's little doubt, however, that Rashid's performance in a clutch moment at The Oval will have assuaged a few doubts, both for the bowler himself and the England selectors, as they weigh up the balance of their side going into a winter of spin-friendly surfaces in Sri Lanka and West Indies.

"England have got so many allrounders in their side," said Warne. "People say England don't need six bowlers, but I like having Moeen Ali in the top six. He's a batsman who plays as a second spinner, so you've really got five bowlers plus Moeen. And that gives you the flexibility to keep Rashid, because I still think he's the best option.

"I like having a legspinner in your side, because you don't pick a side just for the first innings," Warne added. "He might not have to bowl much in the first innings, but in the second innings he might pick up a couple of crucial wickets. And when you've got class fast bowlers, the spinner can be brought on to break a partnership, take a wicket here and there, and then get the quicks back on. And that's okay, because you have to know your role in the team."

Speaking from his own experience, Warne said that Rashid's impact in that first Test, starting in Galle on November 6, could be transformed by the expectation that he will now be an automatic pick for the series.

"You can't explain to someone what it's like when you know you're playing in the next game," said Warne. "If you are playing for your spot all the time it's very, very difficult. You are bowling to not make mistakes. And you're bowling to stay in the team, not do a bad job. To keep it tight.

"If you know you are playing in the next game you have a bit more leeway. You can get a bit more experimental, you'll try a few more things, you'll get a bit more aggressive.

"I think that's what Rashid needs to do. Going to Sri Lanka, he knows he'll play in that next game, which is so important. He's got his confidence up, he got a couple of great wickets in this last Test match to help England win. So I'm looking forward to some big things. Hopefully he'll go on and on from here."