Pakistan's thrilling T20 victory over Afghanistan at the Asia Cup has been overshadowed by a nasty incident between the two sides in the dying stages of the nail-biting clash.

The cricket world was left stunned after Afghanistan bowler Fareed Ahmed and Pakistan batter Asif Ali came face to face after the latter's dismissal.

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Ahmed seemed to have some choice worlds for Ali after dismissing the Pakistan batter to but Afghanistan in a commanding position, needing one more wicket to win with Pakistan requiring 12 runs from nine deliveries for a successful run chase.

Ali top-edged a bounced to short fine leg, with Ahmed coming down the pitch in celebration before screaming in the dismissed batter's direction.

A shove from Ali was met with more words from Ahmed, before the Pakistani turned once more and raised his bat towards the bowler, prompting Afghanistan fielders to rush in and separate the pair.

Fans were stunned by the footage on social media, and even more alarmed by violence among the crowd after the match, which saw spectators hurling chairs at one another.

Footage showed fans ripping seats off their mountings and throwing them at other and and even onto the ground, with others using them to attack spectators directly.

It was an undignified end to what had otherwise been an enthralling contest, the 19-year-old Naseem Shah clobbered consecutive sixes off fast bowler Fazalhaq Farooqi off the first two deliveries of the final over to take Pakistan to 9-131 and the victory.

In a Super 4 game dominated by bowlers, Pakistan's pace bowlers and spinner also did well to restrict Afghanistan to 6-129.

Shah had earlier clean bowled captain Mohammad Nabi for a golden duck to finish with 1-19.

Pakistan's win also ended India's slim chances to reach Sunday's final.

A jubilant Shah threw away his helmet and batting gloves while sprinting toward the dressing room once his last hit sailed over long off and his teammates also rushed onto the field to celebrate the breathtaking win.

"To be honest, it was quite a tensed environment in the dressing room," Pakistan skipper Babar Azam said.

"I was in the dressing room ... I thought it is cricket and I have seen Naseem bat like this, so I had a little bit of belief."

Pakistan edge out Afghanistan in thrilling Asia Cup T20 clash

Left-armer Farooqi had put Pakistan on the back foot when he trapped Babar leg before wicket for a golden duck and then struck twice in his penultimate over before bowling two full tosses to Shah in the last over to end up with 3-34.

Babar has struggled in the Asia Cup after his four straight below-par scores of 10, 9, 14 and 0, but Pakistan's middle-order has done well in run chases.

Leg-spinner Rashid Khan (2-25) had newly No.1 T20 batter Mohammad Rizwan lbw before Shadab Khan (36) and Iftikhar Ahmed (30) steadied the chase with a 42-run partnership.

But Afghanistan didn't give up in the death overs and claimed six quick wickets once Fareed Khan (3-31) had Iftikhar caught at deep midwicket in the 16th over.

Shadab also went down in the next over as he top-edged Rashid to backward point after hitting the leg-spinner for six, but could not resist going for another big hit.

Earlier, after being put in to bat, Rahmanullah Gurbaz and Hazratullah Zazai perished against Pakistan pace inside the batting powerplay.

Spinners Mohammad Nawaz (1-23) and Shadab (1-27) stemmed the runs in the middle overs as Afghanistan struggled to accelerate.

Shadab claimed the key wicket of Najibullah Zadran (10) and Haris Rauf varied his pace in the death to finish with 2-26 as he got rid of top-scorer Ibrahim Zadran (35).

"The boys were brilliant with the ball and in the field, but again we didn't finish well," Nabi said. "We didn't control our nerves at the end. We gave two options to the bowlers, slower balls and yorkers, and sadly we couldn't execute it when we needed to."

With AAP

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