Open Champion has warned Rory McIlroy he runs the risk of long-term injury hitting the golf ball too hard off the tee.

McIlroy could be sidelined for up to six weeks as he recovers from a cracked rib and the result of what the four-time Major winner said was ‘excessive’ practice ahead of teeing-up last week in the BMW South African Open.

The Northern Irishman underwent daily treatment and was constantly taking pain-killers but then still managed to play 72 holes and three extra play-off holes before losing to England’s Graeme Storm.

Henrik Stenson delivers timely warning to the likes of Rory McIlroy and Jason Day.

And while McIlroy was known to have had his upper back strapped during the South African event, it was till Monday when he attended a specialist in Dubai that a scan revealed the World No. 2 had cracked a rib.

“Obviously I’m a bit older before I had picked up the injuries, which must mean that I’m a much better athlete and much stronger than those young guys getting injured,” he said smiling.

“No. You see how hard both Jason and Rory goes after it. Not that I necessarily just pat it myself, but they really go after it, and of course, that’s going to put a lot of pressure on knees and back and neck and so on.

“So yeah, you’ve got to watch it. I mean, they are working hard on their fitness, as we know.

“And the advice I would give to the next generation coming out is just making sure that you work hard from the beginning on your fitness. A lot of guys do, not everyone, but it’s definitely — it doesn’t show up normally when you’re 20, 25. It comes at a later stage. That’s when you’re paying for the wear and tear and a very one-sided motion that we do.

“But if you’ve got more injuries now, possibly a little bit more because of the way everyone tries to hit it and get it a far distance off the tee, of course that’s going to give you the chances of being injured a little bit more.”