Anthony Joshua has his eyes on a future showdown with Tyson Fury after winning the IBF world heavyweight title on Saturday with a sensational second-round knockout victory over US rival Charles Martin. British Olympic champion Joshua, 26, said a bout with Fury was now inevitable but he is being lined up by promoter Eddie Hearn for a first title defence at Wembley on July 9, the same night rival world heavyweight champion Fury is due to meet Wladimir Klitschko.Joshua floored American Martin twice with a right hand to the jaw in a win that earned him the IBF title in front of 20000 fans at the O2 Arena in London.Martin, making a first defence, became Joshua's 16th victim by knockout from as many professional fights.Joshua, who made his professional debut in 2013 after winning Olympic super-heavyweight gold at London 2012, has exchanged insults with Fury on social media and there is already a clamour for the pair to meet.Immediately after the fight, Fury, who says he bet £1000 on Joshua losing against Martin, tweeted:"So AJ gets a belt, but he looked slow and ponderous, and still looked like a bodybuilder. Let me slay the lamb."Apart from Fury, former WBAheavyweight champion David Haye is also making it known he wants to fight Joshua.American Deontay Wilder, 30, who defends his WBC title against Russian Alexander Povetkin in Moscow on May 21, is the other world champion along with Joshua and Fury."Me, Tyson Fury and David Haye - we have to fight," Joshua told a news conference."We can't get through this era without fighting. It's just bound to happen at some stage."Fury, 27, must first prevail over Klitschko in a rematch in Manchester before thinking about meeting Joshua.Of Joshua's first title defence, Hearn said: "It was always going to be July 9. We'll have to take a look at the top 15 of the IBF heavyweight rankings; a lot of the guys are taken up."If he's ready, I don't see why we can't get back early July. That's the plan."Hearn thinks Fury or Haye are still two or three fights away from a bout with Joshua."I'm not saying Haye and Fury are next but they are on the radar and the pressure will be on us after a defence or two," said Hearn.Joshua, meanwhile, insists he will never get complacent as champion after beating Martin, who won the vacant IBF belt after Ukrainian Vyacheslav Glazkov injured a knee in the third round in January."I just feel a bit hungrier," Joshua said. "Getting there is one thing but maintaining it will be harder. I'm diligent and I'm not going to let people down."Probably when I retire I will be happy but I've got to put this behind me now. In training I've developed a different level of stamina. A new man was born."Martin, 29, admitted he could not deal with Joshua's power and said he lost his title, which he only won in January, to the "better man"."I got hit by a right hand I didn't see and that cost me the fight," said Martin."I was okay but the referee came over at six, I got to the knee at seven, took a breath and when I stood up he was at 10."He's a great fighter, it was just that his right hand was fast, I didn't see the right. He's got good speed." ..