Where would the Delhi Capitals be without Marcus Stoinis?

It's a rhetorical question, but if you really wanted an answer, they probably wouldn't be in the IPL final without him. He has brought explosiveness to a batting line-up that has often struggled to get out of second gear, and he has been a handy plugger of gaps with the ball, regularly bowling the difficult overs.

On Sunday, against the Sunrisers Hyderabad, Stoinis pulled off yet another hugely influential all-round performance, and he did not just score runs and take wickets. He also made the Capitals look like a better-structured, better-balanced team.

It began with Stoinis opening the batting, which he has done before - most notably on his way to topping the BBL run charts last season - but only three times in the IPL, back in 2016. At the start of the season, it had seemed unlikely that he would get a chance in that role again, given the Capitals' wealth of top-order options. However, with Prithvi Shaw's form falling away and Ajinkya Rahane not providing the necessary dynamism when he opened, the possibility opened up.

It might have come to nothing if Jason Holder had caught Stoinis off Sandeep Sharma when he was batting on 3 off 5 balls. The move might have gone the way of the Royal Challengers Bangalore opening with Virat Kohli in their Eliminator on Friday - a good idea that got just one, belated chance, and didn't come off.

But Holder couldn't hold on, and we got to see exactly what Stoinis the opener can do. It was much the same as Stoinis the end-overs hitter, as it turned out, but with the added benefit of powerplay field restrictions. The baseball-style swat over midwicket in the fourth over, off Holder, would have brought him six runs in any phase of the game, but the field restrictions also allowed Stoinis to pick up boundaries in other situations that might have only brought him singles or twos outside the powerplay.

Sandeep, for instance, bowled inswing to him with a 5-4 leg-side field, but with only two fielders allowed on the boundary, he had fine leg and midwicket up in the circle. When he strayed off-line in the third over, Stoinis could flick him for back-to-back boundaries. In the fourth over, Holder bowled with his mid-on up, and Stoinis gave him the charge and clubbed him to the left of that fielder even when he tried to pull his length back.

The stillness and balance that have characterised Stoinis' batting right through the season pervaded his game on Sunday too, and that form combined with serious attacking intent to create a potent cocktail.

Stoinis did not survive for too long against Rashid Khan, though, and that was not unexpected. In the IPL, Stoinis' record against spin (average 26.08, strike rate 123.71) is significantly worse than his record against pace (32.00, 147.55). But by opening with Stoinis, the Capitals can ensure he faces less spin early in his innings, or force their opposition into bowling spin at him and shield other batsmen down the order from unfavourable match-ups.

Stoinis has performed this shielding role quite often with the ball - in the game against the Kolkata Knight Riders, for instance, Axar Patel bowled just one over against a left-hander-heavy line-up - and he did so again on Sunday, when the Sunrisers had two right-handers at the crease for long periods and R Ashwin bowled just one of the first 14 overs.

When that happens, one of the fingerspinners often does not complete his quota, leaving Stoinis to bowl at the death. His economy rate has suffered as a result, but he has also made crucial interventions - the miraculous (or lucky, depending on your point of view) final over against the Kings XI Punjab in the Capitals' season-opener, for example, or the final-over yorker to bowl Rahul Tripathi in a high-scoring contest in Sharjah. Stoinis, in fact, has taken wickets this season in the last over of the innings - only one other bowler from any team, Kagiso Rabada, has taken as many.

Stoinis did not have to bowl the 20th over on Sunday, but of his three overs, one was in the powerplay, and one at the death. It was in those two pressure overs that he made his biggest impact.

When he came on to bowl the fifth over, the Sunrisers seemed to be shrugging off the early loss of David Warner, with Priyam Garg and Manish Pandey having put on 24 in 17 balls. By the end of that over, Stoinis had dismissed both of them.

Wickets often fall for no rhyme or reason in T20s, but Stoinis can take some credit for those two dismissals. Garg had looked comfortable on the back foot through his brief innings - he had even hooked Anrich Nortje for six - but his front-foot stride had been minimal when the ball was pitched up. Stoinis tested this with a full ball delivered at 135kph - a significantly quick delivery by his standards - and burst between bat and pad.

Pandey looked to loft Stoinis straight and ended up hitting straight to mid-on, and this was at least partly because Stoinis had bowled an offcutter that gripped and deviated into the batsman, causing him to hit the ball with the inside half of his bat.

When Stoinis began the 17th over, the Sunrisers needed 51 off 24. Kane Williamson and Abdul Samad had put on 49 in 26 balls. Off the fifth ball of the over, Stoinis made his most decisive breakthrough, with a full, wide slower delivery that began just inside the tramline at his end and finished just outside the tramline at the other. The ball was floating away from Williamson throughout, and if he had left it alone, it probably would have been called wide.

Williamson did not leave it, though. The required rate in such situations often compels batsmen to keep going hard, and Williamson reached out to try and pick the gap to the left of deep cover. In reaching out so far from his body, however, he lost control of his shot, hitting it straighter than he wanted and too close to the man on the boundary.

Stoinis roared, arms in the air, fists clenched, veins popping in his granite forearms. He looks like a comic-book superhero, and sometimes he bats and bowls like one too.

Karthik Krishnaswamy is a senior sub-editor at ESPNcricinfo