I've always known Andy Murray is a competitive guy but it's gone to another level in the Athletes' Village this week.
We have a six-bedroom apartment for the male tennis players and there's an ongoing challenge to see who can collect the most pin badges from different nations.
The Village is too big to walk through, so some of the guys take the bikes and cycle around and see how many overseas badges they can get. It's the biggest talking point over dinner and Andy's been using his fame to an unfair advantage. Everyone recognises Andy so they ask him for a selfie and he grabs their badge in return. The rest of the guys don't stand a chance!
You attach them to your accreditation lanyard and Andy's must weigh a ton!
Some badges are harder to find than others. The badges from the smaller nations are rarer and Andy came back to the apartment the other day boasting that he had a badge from Guam, the tiny island in the Pacific Ocean that has eight athletes here.
Andy Murray (pictured) is winning Team GB's competition to see who can collect the most pin badges from other countries in the Athletes' Village
But Andy (right) has been using his fame to an unfair advantage. They ask him for a selfie and he takes a badge from them in return
That competitive edge is one of the reasons why he's enjoyed such a successful career
All jokes aside, that competitive edge is one of the reasons he's enjoyed such a successful career. I'm in an incredibly privileged position to be his doubles partner for his final event before his retirement, and we've been training together every day. It's been our priority over the singles.
We were in the van to training on Tuesday when he announced his retirement on social media. Andy was on his phone in the front seat and his post suddenly popped up on my Instagram feed. I had an idea it was coming but the timing took me by surprise. It hits home when you see it in writing.
At the time, I didn't say anything about it. I just thought, 'Right, let's practice'. Our session was no different to normal, except for the army of cameramen and women who suddenly turned up. As has been the case throughout his career, missing a return in training is not part of Andy's ethos. I've never met anyone who hates making a mistake as much as he does and that's not changed here.
He wants to hit every ball and that mindset is part of what's made him such a good player.
We were in the van to training on Tuesday when he announced his retirement on social media
I had an idea his retirement was coming but the timing took me by surprise - it hits home when you see it in writing
As has been the case throughout his career, missing a return in training is not part of Andy's ethos
We have been adapting our game for doubles. The key thing in doubles training is familiarising with each other on the court, getting our systems and getting our plays right.
It's about knowing where to hit the ball, when to cross, when to intercept, when to defend and when to attack.
There's only half the court to play into so it's very different to singles.
My knee hasn't been quite right since I slipped at Queen's last month and the doubles is easier on the body, because there's less ground to cover.
I'm happy with our preparation and we want to go home with an Olympic medal.
On a personal note, it would be the best achievement of my career. It's different to winning a Grand Slam, which I have never done, but the Olympics is seen as a very high accolade on the tennis circuit.
Even though this is Andy's last tournament, he wants to win more than anyone. That's evident in training.
My knee hasn't been quite right since I slipped at Queen's last month and the doubles is easier on the body
What he's achieved throughout his career is incredible and he's right in the conversation of Britain's greatest ever sportsperson
Andy does not see Paris as a grand farewell event. His idea of a farewell is being on a medal podium
What he's achieved throughout his career is incredible and he's right in the conversation of Britain's greatest ever sportsperson. For me, he's up there with Lennox Lewis, Wayne Rooney, Lewis Hamilton and Paul Gascoigne. It's a pretty good conversation to be in and the scale of the occasion is not lost on me.
Andy doesn't see it as some grand farewell event. His idea of a farewell is being on a medal podium and that's what I've got to try to do for him.