Monster Obstacle Help?

[master pes 4]

I may be a mile off here but does anyone think that you might have to hit 20 Monster Obstacles in one race? Like quite alot of you I have been through every race on Normal about 3 times and still dont have the achievement. So I think that you go onto the race with the hangers and try and count up to 20 monster obstacles hit and see if that works?

[NeonInVermont]

No, its not in one race.
I was going through all levels to get the achievement and as soon as I hit the bridge the achievement poped up. I was on my first lap so there is no way I would of got 20 already. As soon as I hit it, like 5sec later the achievement poped up.