It's homespun and ungainly, it leaves Samiullah Shenwari on his backside, but it's spectacularly effective. It's more a reverse swipe than a reverse sweep, but he knows third man is in the circle, and Thisara Perera bowls him a ball giving him just enough width to exploit that fact. Shenwari falls to the floor, the ball races away between wicketkeeper and short third man, and Sri Lanka are rattled.

Shenwari departs in the next over, but his 14-ball 31 has transformed Afghanistan's innings. They were 51 for 4 in 11 overs when he walked in, and by the time he's dismissed, they are 112 for 5 in 16.3. They end up scoring 102 runs in their last nine overs, and but for sloppy fielding could have beaten the defending champions.

That innings came in the middle of a solid run of consistency at the World T20: Having not had to bat in Afghanistan's first two matches, Shenwari made a critical 37-ball 43 in a virtual play-off against Zimbabwe, and followed it up with that 31 against Sri Lanka, a 14-ball 25 in a big run-chase against South Africa, and a 27-ball 22 in the midst of a collapse against England.

Given the fact that he's also bowled 18 overs at an economy rate of 6.44, Shenwari's stats push forward a case as a candidate for Afghanistan's tournament MVP. He's also a leading candidate for their all-time MVP: he's one of only three batsmen with a 30-plus batting average in ODIs, has the most 50+ scores in ODIs for Afghanistan with 10 and is their fourth-highest wicket-taker in both ODIs and T20Is - behind Mohammad Nabi, Dawlat Zadran and Hamid Hassan - and has faced more deliveries than any other Afghanistan batsman in ODIs and T20Is combined.

That last statistic is not surprising, given his role in the side. "Always they give me the job to stay on the wicket," he says. "No need [to worry about] your runs and everything, just stay on the wicket, you can do it."

It's a batting instruction that recognises Shenwari's ability to handle pressure, adapt to different situations, and work out a method to move his team forward. These qualities were fully in evidence in his two finest international innings, which, by no means coincidentally, led to two of Afghanistan's greatest cricketing moments: their first ever ODI win over a Test-playing team, against Bangladesh in Fatullah at the 2014 Asia Cup, and their first ever win at the World Cup, against Scotland in Dunedin last year.

Afghanistan overcame enormous pressure in both those matches. In Fatullah, they were 90 for 5, in 26.5 overs, when Shenwari walked in to join Asghar Stanikzai. In Dunedin, Shenwari was batting on 24 when they slipped to 97 for 7 while chasing 211.

Against Bangladesh, Shenwari made 81 off 69 balls, Stanikzai scored an unbeaten 90 off 103, and their 164-run partnership - a sixth-wicket record stand for an Associate country, breaking the mark of 162 set by Kevin O'Brien and Alex Cusack against England in the 2011 World Cup, and sixth-highest sixth-wicket stand for any country in ODIs - lifted Afghanistan to 254. They eventually won by 32 runs.

"I'm looking forward to be there in the IPL in the next two years," he says. "Everyone in the world is looking forward to playing the IPL."

Against Scotland, Shenwari scored 96 off 147 balls, shepherding Dawlat Zadran first and then Hamid Hassan in partnerships of 35 and 60 spanning a total of 23.1 overs for the eighth and ninth wickets, before being dismissed with 19 runs left to get from the last 19 balls. He remained crouched just behind the boundary line, still-helmeted head in his hands, as Hassan and Shapoor Zadran sneaked Afghanistan to a one-wicket win.

In both games, Shenwari said essentially the same thing to his batting partners: just stay at the crease.

"I will do everything, just stay on the crease," Shenwari first told Dawlat, then Hassan, against Scotland. "I talked to them, I told them, 'Just five overs you need to stay on the wicket. Even if we get 10 or 15 runs it's enough. No need to be in a rush.'"

There was none. In a chase of only 211, Afghanistan seemed to be slipping out of contention when they required 9.50 runs an over at the 46-over mark, but Shenwari had calculated which bowler to target. He waited until offspinner Majid Haq's final over to hit him over the top, with the turn, smashing him for three sixes before holing out while going for a fourth.

In the Bangladesh game, Shenwari and Stanikzai came up with a similar plan.

"The wicket was very good, and I read the wicket, how the ball is coming, read the bowlers, which one should I target, which one should I not," Shenwari says. "Our plan was just [wait and watch until] last 10 overs, nothing more," Shenwari says. "Till we have wickets in the end, we can do whatever. If we have wickets with us, we can do 100 runs in last 10 overs, easy." Having made 147 in their first 40 overs, Afghanistan walloped 107 in their last 10.

There is something of MS Dhoni in Shenwari's calculated approach, his willingness to minimise risk till the closing stages of one-day innings, and even in his technique: he's a powerful, bottom-handed ball-striker, and loves to stand in his crease and carve the ball through the off side, and he doesn't take a big stride forward while defending or playing the drive. He says Inzamam-ul-Haq, Afghanistan's coach, is working hard on improving that aspect of his game. "While driving, [he tells me], go on the front foot, don't just stay standing."

For all the similarities with Dhoni, it is Virat Kohli he name-checks when you ask him which batsmen he likes to watch. "He's the same like me," Shenwari says. "He stays on the wicket, anyone gets out or whatever."

The bowling hero is rather more predictable. "I looked up to Shane Warne from the beginning," he says. "I like him and I would love to meet him."

Shenwari genuinely turns his legbreaks, though not with Warne's level of control, and says he also bowls a flipper, and shows how he squeezes it out of the front of his hand. He says he learned this delivery, and the art of legspin in general, by watching videos of Warne and Mushtaq Ahmed.

The fundamentals of his bowling action look sounder and less homespun than his batting technique, except for the dainty hop he performs after taking the first step of his run-up. It is, like his slog-sweep and that slash through point, a distinct stamp he leaves on the Afghanistan team.

It is hard to say when Afghanistan will next get a chance to play an ICC event, and like his team-mates, Shenwari hopes more Full Member teams will arrange bilateral fixtures against them. He also thinks playing four-day cricket in the Intercontinental Cup has helped Afghanistan's game in all other formats - "when we play four-day cricket, the T20 and one-day for us look very easy" - and hopes his team can play Test cricket one day. At a more immediate, personal level, there is one other thing he would really like.

"I'm looking forward to be there in the IPL in the next two years," he says. "Everyone in the world is looking forward to playing the IPL."