Allen, who won the tournament in 2016, took his 11th world ranking title with a 10-8 victory in Telford that lasted more than seven hours.

"It was tough all day," Allen told ITV4. "My safety kept me in the match, but it wasn't a lot of fun to be involved in.

"I've won five (ranking titles) in the last couple of years. I want to keep doing that and if I can get to 20 or 30 at the end of my career I would have done all right."

Allen secured his spot in the final with a 6-3 victory over Ali Carter, while Zhang held his nerve in a last-frame decider against Mark Selby in their semi-final clash.

Despite Zhang's domination in the opening frames, Allen managed to claw his way back into the match to level at 4-4 going into the evening session.

Allen managed to gain momentum, winning three frames in succession to claim a 8-6 lead, and eventually sealed victory as the clock ticked towards midnight on Sunday.

The Northern Irishman picked up where he left off after fighting back in the afternoon.

Allen took the lead for the first time in the match at 5-4, but Zhang instantly responded and a break of 64 in the 11th frame gave him a 6-5 advantage.

Zhang was pegged back again as Allen made a 64 break and a missed pink cost him dear in the next.

The see-saw nature of the contest continued as Zhang fought back to take the 15th frame and Allen showed his strength again in the 16th before a marathon 17th.

The frame took 37 minutes before Zhang, who had chances to sew it up some time before he did, eventually potted the pink off a cushion.

Allen wore Zhang down in the next as breaks of 40 and 24 proved decisive, with the Chinese player failing to score a single point in what proved to be the finale.