Betting Against Injured Tennis Players: Why It's Usually a Mistake

How Griekspoor Beat Rublev While Barely Walking

On Friday, Griekspoor beat Rublev in the Dubai semifinals 7–5, 7–6. It was his first victory, on the fourth attempt. The thing is how Griekspoor beat the Russian.

Griekspoor picked up a left hamstring strain at 6–5 in the first set, but after taking a medical timeout off the court, he came back playing very aggressively. After that, he could barely walk, but he managed to break Rublev’s serve and win the first set.

In the second set, despite winning only four return points the entire set, he held his own serve, saved the break points he faced, saved two set points in the tiebreak (one on Rublev’s serve), and went on to win both the set and the match.

He probably would have retired if Rublev had won either of those two set points. Rublev was defeated by a player who was injured and playing with nothing to lose.

Afterwards, the Dutchman said: “After that game at 6–5 in the first set, if he had held and won the tiebreak, I don’t know if I would have continued.”

The Expensive Lesson I Learned Betting Against Injured Players

The real point of this email is about betting live against injured players.

In the early years of my betting career, I lost a lot of money doing exactly that — betting live against players who looked injured.

I thought I was very clever, watching matches live and betting against any player at the slightest sign of discomfort.

And yes… the great Monfils, who will leave us this season, was number one on that list 🙂. How many times have we seen him look completely done — barely able to play one more point — only to recover and win the match?

The last one I remember was Tsitsipas vs. Medjedovic last year. I didn’t bet live that time, but I had a pre-match bet on Tsitsipas — and he lost to a player who was literally limping. Medjedovic withdrew from the tournament right after that match.

So yes, I don't have the numbrs but I'm pretty sure I lost quite a bit over the years betting against “injured” players — and I’m sure some of you have gone through the same, haven’t you?

However, over time, I’ve become more and more convinced that betting live on players who seem to be struggling physically — cramps, injuries, whatever — can actually be profitable in the long run.

Impossible to prove, yes — but I have no evidence and no doubts either. 🙂

Why "Injured" Players Win More Often Than You Think

But why do “injured” players win so often?

Not every injury is as bad as it looks. Some players complain more than others, some exaggerate, and sometimes what seems serious isn’t. Faking or exaggerating an injury can also help them feel relieved. I remember a match of Gaël Monfils where it seemed impossible to me not only that he could keep playing, but even that he could walk to his chair. And he won that match. And in this case, I don’t think the Frenchman was faking it at all.
The opponent’s mindset shifts. Playing against an injured rival is uncomfortable — you don’t know whether to stay aggressive or just keep the ball in. Also, you have little to win and much to lose. The pressure completely shifts against you.
The injured player feels free. They have little to lose, so they relax, swing freely, and often start playing better — many times hitting winner after winner. With no pressure, they go for their shots.

The Takeaway: Think Twice Before Betting Against Injured Players

So yes — in my opinion, live odds tend to overreact to apparent injuries, and a cold, rational bettor can often take advantage by backing the injured player.

That’s easy to say, but very difficult to do when you’re watching the match.

It’s a bit illogical… you see a player struggling, and betting on him — no matter how high the odds are — isn’t easy.

In this case, the injury was in fact as bad as it looked. Griekspoor could not play the final against Medvedev and will be out of the circuit for several weeks. But the second and third points happened.

Rublev looked surprised and missed all six break points he had in the match. And he also wasted 2 set points.

Also, Griekspoor felt completely free, with nothing to lose, going for his shots.

I couldn’t see the live odds during the Griekspoor–Rublev match, but surely they were very low for Rublev and very high for Griekspoor after he got injured.

So be careful when betting live against players with physical issue. The market is probably overreacting, and the value may actually be on their side — not on their opponent’s.