Asif Ali's clutch 26-run cameo under tense conditions helped Islamabad United defeat Peshawar Zalmi by three wickets and claim the Pakistan Super League 2018 title at the National Stadium Karachi on Sunday.

After winning the toss and opting to bat first, Peshawar Zalmi sent out the pairing of Kamran Akmal and Andre Fletcher to open their innings, whereas Samit Patel and Mohammad Sami shared the new ball for Islamabad United.

After two quiet overs, things livened up in the third as Fletcher hit back-to-back fours off the bowling of Patel.

Zalmi were dealt a huge blow in the third over when the in-form Akmal departed. Patel had him trapped in front of the wickets and even though he took a review; he failed.

Mohammad Hafeez walked in to join Fletcher in the middle.

The Professor hit the most effortless of 6s in the 4th over bowled by Sami before sent packing by Patel on the first ball of the 5th. Here's that sequence:

Five overs into the final, Zalmi were 36-2 -- not the kind of start they would have wanted in the most important match of their PSL 2018 campaign.

And they were soon given another jolt. Shadab Khan was introduced into the attack in the 6th over and he struck almost instantly, sending Fletcher back into the dugout.

But Chris Jordan looked in good touch. He hit a six each in the 8th, 9th and 10 overs.

Halfway through their innings, Zalmi were 73-3, with Jordan and Liam Dawson at the crease.

Here's the view from the press box from where Dawn.com sports team is covering this match live.

Jordan hit another maximum before his 36-run innings came to an end in the 13th over.

Zalmi brought up their century in the 14th over but were dealt another setback in the follow-up over when Hussain Talat removed Saad Nasim.

With just 5 overs left in their innings, Zalmi were 110-5 and in desperate need for some late fireworks from their captain Darren Sammy and Liam Dawson.

The curse of Nelson was there for all to see as Zalmi lost two batsmen at the score of 111. First Sammy (6) fell prey to Shadab before Umaid Asif met the same fate.

Here's the official PCB scorer, Mohammad Imran, keeping an eye on every run scored, every wicket taken.

The wickets kept on tumbling but Zalmi did just enough to put 148 runs on the board for the loss of 9 wickets in their allotted 20 overs. They owed a great deal to Wahab Riaz's late cameo (28 runs off 14 balls).

They had successfully defended the same total in last year's final and considering the bowling options at Sammy's disposal, there was no doubting that they could do it again.

The run chase

The new ball was tossed to Hasan Ali, who bowled a trio of decent balls before Luke Ronchi's rampage began. He hit the pacer for two consecutive sixes to cement Islamabad United's position as the favourites in the match.

The hard-hitting kiwi smacked another maximum off Sameen Gul in the second over, mesmerising the Karachi crowd but chipping away at the hopes of an evenly contested game.

Sahibzada Farhan played the facilitator's role as Ronchi shellacked Zalmi bowlers one after the other.

By the end of 5 overs, United were 63-0 and cruising towards the title.

United wouldn't lose their first wicket until the 9th over when Jordan had Ronchi (52 off 26 balls) caught. The New Zealand departed having scored his 5th half-century of the tournament.

Having lost their first wicket in the 9th, United stuttered a little, losing two more batsmen -- Chadwick Walton and JP Duminy -- in as many overs. But by the end of the 11th over, they were 106-3 and needed just 43 runs off 54 balls to reclaim the PSL title.

Farhan's 44-run knock also came to an end in the 12th over as United started to get a bit nervy.

The 13th over was uneventful before another wicket fell in the 14th as Zalmi threatened to turn the game on its head.

In that same over, Hasan Ali picked up another wicket, with Shadab Khan departing. Jordan's diving catch was worth watching.

Zalmi could have had another wicket had Akmal not dropped Asif Ali's catch on the penultimate ball of the 15th over.

With just 5 overs left in PSL 2018, United needed 23 runs and had four wickets in hand.

A hero was needed and Asif Ali decided to volunteer. He smashed three sixes in a tensed situation. His six-ball 26-run cameo, laced with three 6s, saw United through.

There was plenty of fireworks after the winning shot. WHAT A NIGHT!

United, the inaugural PSL champions, had reclaimed their title. Luke Ronchi received player of the match award, and boy didn't he deserve that.

Pre-match proceedings

Dawn.com is at the stadium to cover the match live for our readers. We're sat just behind the VVIP gallery; lots of security, lots of famous faces here.

The opening ceremony ahead of the final has ended. The podium has been disbanded. The stadium is packed to the rafters and the players are all warmed up.

Explore: Music and festivities as PSL 2018's grand finale kicks off in Karachi

Both the squads have lined up for a pre-match team photo.

The entire stadium stood up to pay their respect when the national anthem was played.

Line-ups

Peshawar Zalmi: Kamran, Fletcher, Hafeez. Nasim, Dawson, Sammy, Jordan, Hasan Ali, Wahab, Umaid, Sameen Gul

Islamabad United: Ronchi, Walton, Duminy, Farhan, Hussain, Asif, Khan, Faheem, Ammad Butt, Sami, Patel