CARDIFF: New Zealand skipper Kane Williamson won the toss and elected to bowl first against Sri Lanka in their opening World Cup match in Cardiff on Saturday. Paceman Tim Southee missed out due to a calf injury as the Kiwis -- runners-up in the 2015 edition -- went in with two all-rounders in their starting line-up. Batsman Henry Nicholls was also injured, with Mitchell Santner the only spinner in the side. "Just a one spinner and two all-rounders. That helps with the balance," Williamson said at the toss. Sri Lanka captain Dimuth Karunaratne admitted he would also have bowled first to take advantage of the green tinge on the pitch. "I would have bowled as well. We wanted to take advantage," said Karunaratne, who has returned to the side after missing out on four years of one-day cricket. "We don't have much pressure. We want to do well. We want to show what we can do." Sri Lanka, World Cup winners in 1996, are ninth in the one-day rankings and have been given little chance in the 10-team tournament. Teams: New Zealand: Kane Williamson (capt), Martin Guptill, Colin Munro, Tom Latham (wkt), Ross Taylor, James Neesham, Colin de Grandhomme, Mitchell Santner, Lockie Ferguson, Matt Henry, Trent Boult Sri Lanka: Dimuth Karunaratne (capt), Lahiru Thirimanne, Kusal Perera (wkt), Kusal Mendis, Angelo Mathews, Dhananjaya de Silva, Thisara Perera, Jeevan Mendis, Suranga Lakmal, Isuru Udana, Lasith Malinga