BRISBANE (Reuters) - Mohammad Irfan was back to his best as Pakistan had to rely on their bowlers to get their stuttering World Cup campaign back on track after yet another dismal batting performance against Zimbabwe at the Gabba on Sunday. Fast bowler Irfan, standing a lofty 2.16 metres (7-foot-1-inch) tall, was the pick of the bunch and inflicted a lot of the damage with his career-best figures of 4-30 in the 50-over format. Zimbabwe were chasing a paltry 236 for their second win of the tournament and a brisk start from their openers would have set them up well with the likes of Hamilton Masakadza, Brendan Taylor and Sean Williams to follow. But a hostile opening spell from the 32-year-old left-arm paceman pushed Zimbabwe firmly on the backfoot. Irfan dismissed openers Chamu Chibhabha (nine) and Sikandar Raza (eight) with sharp, rising deliveries in his opening spell and the batsmen rarely looked comfortable against the steep bounce he extracted off the Gabba surface. I was concentrating on my line and length when I started. I asked the batsmen to make mistakes which they did, Irfan told the broadcasters. Since I was not bowling well in the earlier matches. I had to cut down on my pace to concentrate on my line and length. But now I have got used to (the conditions) so the pace is also increasing. With the total we had we could not afford to let them get a good start. The plan was to attack and also keep the runs down. After Junaid Khan and Umar Gul were ruled out in the lead-up to the tournament with injuries, Pakistan have relied heavily on Irfan to provide breakthroughs with the new ball. He delivered almost every time he was called upon by captain Misbah-ul-Haq. A well-set Masakadza (29) and Taylor (50) had just completed a 50-run stand for the third wicket when Misbah decided it was time to bring Irfan back. Masakadza holed out on the second delivery of his second spell while Solomon Mire (eight) edged one to the wicketkeeper in the first over of his third. The rhythm, however, was clearly lacking from Irfan's bowling in Pakistan's first match when he leaked 58 runs without a wicket in his 10 overs during the defeat to India. In the loss to West Indies that followed, he fared little better, only claiming the wicket of the dangerous Chris Gayle and conceding 44 runs. Yet he was back in form on Sunday. He showed his class today. Possibly we could have left the ball a little bit better, Taylor, who top-scored for Zimbabwe, told reporters. He does make it a handful for you.