PALLEKELE (AFP) - Pakistan coach Waqar Younis Saturday warned under-performing opening pair M Hafeez and Ahmed Shahzad to start delivering World Cup runs. "We have to show real improvement in our batting, especially our openers who have not done well," said Waqar. Pakistan defeated Canada by 46 runs in their last match, after being bowled out for a disappointing 184 against the Group A minnows. Hafeez and Shahzad, who both showed good pre-tournament form, have managed partnerships of just 11, 28 and 16 in three matches so far, starts which Waqar feels put the middle order under strain. "Both openers know they have not fired yet, but I'm not worried because there is no problem with their techniques, they were in good form coming into the World Cup, so I am sure they will come good soon," said Waqar. Waqar said every batsman need to show responsibility against New Zealand at Pallekele on Tuesday. "I think since Misbah-ul-Haq, Umar Akmal and Younis Khan were making runs there was not much pressure but I am sure now after a poor batting show, others will also take responsibility. We need good starts," said Waqar. "We have batted first in all our three matches, so it would be a great test of our batsmen when we chase a target because that adds to the pressure," he said. Despite his reservations over the batting line-up, Waqar has no problems with the Pakistan attack. "Our bowling is doing well and is supporting the batting, but we would have had a serious problem defending a 185-run target against stronger opposition." Waqar praised skipper Shahid Afridi whose leg-breaks fetched him 5-23 against Canada, taking him to a tournament-best 14 wickets. "When Canada were batting well, I was sure that if we got one or two wickets then the gates would open and the way Afridi bowls I'm sure we can defend any good target," said Waqar.