Pakistan's wicketkeeper-batsman Mohammad Rizwan hit a match-winning century against Sri Lanka in Hyderabad on Tuesday, which powered Pakistan to the highest successful run-chase ever in an ICC ODI World Cup match.

Rizwan remained unbeaten on 131 off 121 balls as Pakistan chased down a 345-run target with six wickets in hand and 10 balls to spare at the Rajiv Gandhi International Stadium.

But on his way to a match-winning knock, Rizwan had to battle through exhaustion, back pain and cramps.

In the 36th over of the chase, Rizwan fell to the ground holding his back after seemingly hurting his back a couple of deliveries ago while trying to reach for a wide delivery.

After receiving some treatment from the Pakistan team physio, Rizwan was back on his feet.

In the following over, Rizwan charged down the wicket to Dhananjata de Silva and sent the ball over the ropes through the long-off region. But in the followthrough of that stroke, he collapsed to the ground in a rather dramatic fashion, clutching his right calf.

The physio again rushed to the middle, treated him for the cramps and Rizwan was soon ready to resume his innings.

After the match, when Rizwan was asked about his struggles in the middle after being named the player of the match, the 31-year-old gave a lighthearted response.

"Sometimes cramps, sometimes acting (smiles)," Rizwan said at the post-match presentation.

Rizwan and Abdullah Shafique, who made 113 off 103 balls, formed a 176-run partnership for the third wicket which set up the record chase for Pakistan.

Rizwan revealed that even after losing two early wickets, the Pakistan team believed they could win the match.

"Every player in the dressing room had the belief we can chase that. Basically, it's a good track and we decided to calculate the innings."