Each track in F1 Race Stars has a locked shortcut which requires a key to open it, the player who gets the key and opens the shortcut has a huge advantage in a race. But there are a few things to know about the keys.

First, there is only one key each lap but it always spawns in the same spot. The spawn time depends on the track position of the drivers. I noticed that the keys tend to spawn when position 3+ are close to the location, I never saw one when I already was in the lead, but you can hear a chime sound when it appears.

Going for the key is on most of the tracks risky, because you have to drive a longer or slower route and you probably won't be the only one looking for it. Also if you got one you can loose it again when you get hit with a power-up or through environmental damage (sumos, water splashs etc.). However that's also a chance for you to aquire the key from another player, just hit him with a power up or push him into a bubble or obstacle and he'll drop the key.

Unfortunately you can't defend yourself when carrying the key, because your power-ups are locked. On some tracks it's quite a distance between key location and shortcut entrance, there are even tracks where the key is in the end of one lap and the shortcut at the beginnging of the next lap, so you also need a certain amount of luck to keep it. That's escpecially important for short races, where it's useless to go for the key in lap 2/2 when the locked shortcut is in the next lap.

But if you or someone else looses a key and no one picks it up it definitely is worth to reverse and get it.