Miserly Mark Watt lights up the grubby art of left-arm fingerspin

Left-arm fingerspin is a grubby, unglamorous skill at the best of times but in T20 cricket, particularly so. The majority of its purveyors in this World Cup hardly try to spin the ball, instead bowling defensive lines and lengths in a desperate attempt to escape from their spells unscathed. Few of them have wrong 'uns, instead they rely on arm balls, angles and changes of pace for their variety. Their art is constructing an over, finding a way to string six balls together without becoming predictable.

The poster boy for defensive darts at this tournament has been Mark Watt, Scotland's broad-shouldered, combative linchpin. He has bowled his full allocation of four overs in every game, taking exactly one wicket in each, and has been hit for seven boundaries in total. With games against India and Pakistan to come, he is yet to concede more than 23 runs in a spell.

Counterintuitively for a defensive bowler, Watt's strength lies in his variety. His delivery points are hugely varied, sometimes bowling from a two-pace run-up with a release-point in line with the umpire, and regularly going so wide on the crease from round the wicket that his front foot lands off the cut strip. He regularly bowls at up to 65mph/104kph, and his height helps him generate both good bounce from a good length and dip on his yorkers.

Watt's variety is a natural response to bowling on Scotland's small ground in Edinburgh when they play at home. "Bowling spin at the Grange is quite tough," he said earlier in this tournament. "It's a small round, fast outfield, and a good wicket. If you can bowl spin there, you can bowl pretty much anywhere. You need to think about different variations to keep the batter guessing when it's only fingerspin.

"The wickets you get in international cricket these days, they don't do a lot for fingerspinners," he told Wisden's podcast after Scotland's win against Bangladesh. "It's about trying to keep the batter guessing, trying to keep them watching you all the time, and finding any sort of advantage you can get. White-ball cricket for a fingerspinner is tough.

"It might be a bit cheeky bowling from 25, 26 yards - but if it gets me a dot ball in T20 cricket, I'm going to try and keep doing it. Everyone in the nets tries to hit it to the moon so I was a bit scared bowling it in games but it seems to work: the batter is looking down at his toes, then looks up and the ball is halfway through its flight."

Perhaps the biggest compliment paid to Watt was New Zealand's approach against him in Dubai. He took a wicket with his first ball, having Devon Conway caught behind off the glove while reverse-sweeping, and despite the fact that both Martin Guptill and Glenn Phillips were set for the second half of his spell, New Zealand's batters made only two boundary attempts off him; neither was successful.

His death bowling has been particularly impressive, jamming in yorkers and cramping batters for room: he was entrusted with the 18th over against New Zealand, conceding only five runs - including a leg bye - after nutmegging Phillips with a yorker with his first ball. Watt's figures of 1 for 13 were his best in the tournament to date, and the cheapest four-over spell by a Scotland player in all men's T20 World Cups.

"He just doesn't give a lot," Guptill said. "He wasn't trying to turn the ball necessarily, or anything like that. He's just bowling good lines and lengths, getting inside our arcs so that we couldn't really take him down. He bowled very well and it was just a matter of trying to get through it and not let him bog us down too much."

"Mark was fantastic," Kyle Coetzer, Scotland's captain, said. "He's been bowling extremely well for quite a while now on this whole tour that we've been on. He's been the guy who you can throw the ball to at any end: short boundary or long boundary, into the breeze or against the breeze, he's there and he's willing to do it.

"He's shown that the skill he has and the ability to be able to restrict runs. It's not just about being able to deliver a ball that has some revs on it or might turn, or being able to bowl a good yorker; it's about understanding and reading the game and he has excellent game sense, and showing why he's on this stage. Mark's very aware on who does what, whether players sweep or reverse-sweep, and where they look to hit the ball."

Watt has had two brief experiences playing county cricket, signing a short-term deal with Lancashire in 2018 and playing for Derbyshire for some of the following summer, and since he qualifies as a local player, his performances in this tournament should attract further interest ahead of the 2022 season.

"I think Mark deserves that, as far as I'm concerned," Coetzer said. "He's certainly got the ability to go and play in those competitions - not only the county stuff, but maybe other franchise tournaments around the world. He's certainly put his hand up to be one of the best left-arm spinners in this competition."