Sonic & Mario at the Olympic Games was released a year after Sonic creator Yuji Naka left SEGA, but he claims the idea was all his.
"It was actually my idea," he told a Eurogamer Expo 2010 audience today, "and I was the one who approached Nintendo about it.
"I thought it would be fascinating to see the two heroes play together or play against each other, so that was exactly what I wanted.
"So I don't feel anything funny about that at all," he added.
Yuji Naka was at the Eurogamer Expo 2010 promoting his new Wii and DS game Ivy the Kiwi?, a platformer with a unique draw-and-guide mechanic. It's complicated.
But evidently Naka's a man with many ideas: not only is he interested in new technologies such as Move and Kinect - he's already built games for them.
"Yes I'm very much excited about the new technologies," Naka said. "I'm hoping I can create something exciting using those new technologies.
"Actually," he revealed, "I worked on two games that unfortunately didn't come out and those two games used those two technologies you just mentioned."
The audience's attention, however, was on Yuji Naka as the creator of Sonic the Hedgehog. And as far as that blue creature is concerned, Naka doesn't seem to begrudge SEGA his future use.
"Since I left SEGA I don't really follow the series too closely," Naka revealed, causing ripples of laughter.
"I believe there are many more things that Sonic can do, so I'm very much looking forward to future Sonic series. I believe in SEGA and the Sonic Team as well, so I'm sure they will continue making fascinating Sonic series forever."
What's his favourite Sonic game? "Sonic 1," he said. "That was a title that made me realise I could do something that could make me attract people around the world."