The Ivory Coast striker goes into Sunday's trip to QPR on a run of six in six matches and with 12 goals altogether in his first season in England.
And Martinez is less concerned with Kone's long-term future than the immediate aim of keeping Wigan in the Premier League.
The manager said: "For me he's a sensational footballer, a very important player for us. I would say he has been invaluable. Although he is enjoying the best moments of his career, the best is still to come.
"Over the years we've learned not to focus on trying to keep players. We've been focused on bringing players in who can perform well for Wigan for the duration they are going to be here.
"It's pointless for us worrying about what could happen if we lose him. What I worry about is a player dropping their level of performance, but Arouna has been fantastic at this football club.
"Over the last six games he has been really consistent in what he has been doing. We were delighted we were able to sign him, and now, for however long we are going to have him, we're going to enjoy him on a daily basis."
Martinez believes Premier League status could be secured with fewer than the 37 points needed for safety last season, but the target is to add 10 more to his side's current 30.
He said: "You always know that 40 points guarantees you safety. I do expect it to be a little bit lower than last season because there are more teams involved.
"Sunday's game is a very important one - we are playing against a team fighting to reach same target.
"But if we get three points it doesn't mean we've achieved our aim, and if we don't get three points that doesn't mean we won't achieve our aim."