Josh Johnson breezed through his first session of live batting practice, looking like the ace he used to be. “We’re counting on him,” said manager John Gibbons. “We need him. It wasn’t too long ago he was in the top two or three pitchers in baseball.” Johnson, no doubt, would like to be in that company again, this being his free agent season. Last season was something of a transition year as he made all his starts after two injury-plagued seasons. “In talking to him,” said Gibbons, “I learned he started using his curve ball more and I guess John Buck helped him along with that down in Florida and it’s made a big difference for him. He’s always had that overpowering arm. He’s battled some health problems that I think are now behind him.