Jung Ho Kang (leg) unsure if he'll be ready for Opening Day

Pittsburgh Pirates infielder Jung Ho Kang, who had surgery after suffering a serious leg injury in September, is still unsure whether he'll be ready for Opening Day.

Five months after having surgery to repair a broken bone and torn meniscus, Kang is working out at the team's spring training complex in Bradenton, Florida. He is fielding grounders, making throws and taking swings, but he's unsure as to when he'll be able to play.

"I don't know," Kang said. "Nobody knows. I know it's not 100 percent yet, but I've been working hard. I believe it's going to get better."

Kang suffered the injury when Chicago Cubs baserunner Chris Coghlan crashed into Kang, who was playing shortstop, to break up a double play. The Pirates originally estimated his rehab would take six to eight months.

The 28-year-old Kang, who signed a four-year, $11 million contract in January 2015, finished third in the NL Rookie of the Year voting last season after batting .287 with 15 home runs and 58 RBIs.

"This guy is motivated to be better than he ever was," Pirates manager Clint Hurdle said. "He's done a lot of work. He's come a long way. And the work he's done has been done with great perseverance, and we expect that to continue."

MLB is mulling rule changes that would curb takeout slides. Kang, who was used to a less aggressive style of play in Korea, supports the reforms.

"I think it's a very good idea," Kang said. "It would help protect the players, so I think it's good."

The Associated Press contributed to this report.