Neil Wagner, the New Zealand seamer, will make his debut in English county cricket with Northamptonshire after compatriot Ian Butler's retirement continued a run of bad luck with overseas signings for the county.

Wagner agreed his contract back in May, along with Butler, who made six T20 appearances for Northants. Wagner was expected to be available after the tour to West Indies and might take the field against Nottinghamshire in the Championship game in August.

Wagner had been excluded for the first two Tests, but was a vital component in New Zealand's first major overseas series win since 2002. He has not pegged down a regular spot in the Test side but his tendency to hold one end up and bowl long and tight spells add to his value. He has 362 wickets in first-class cricket at 25.11 with 16 five-wicket hauls. He is two short of 100 victims List A cricket, and has 53 dismissals at an economy of 8.6 in domestic T20s.

David Ripley, the Northamptonshire coach, had wanted to keep Butler for longer but said an injury had forced matters out of hand. Buttler has since called time on his career.

"We signed Ian at short notice, after a third overseas player withdrew, mainly for the NatWest T20 Blast but also hoped he would be able to manage playing in some County Championship games as well," Ripley said. "It's sad to say, that Ian picked up an injury and won't take any further part this season."