Yes A-Rods pants are long. It will be hard to match that, as his are custom made. You will need extra long pants, probably professionally lengthened to match the look. Or a couple sizes too big, and tighten your belt.
As you are playing, there are 3 ways to keep them down, and in place.
1. You can sew elastic to the bottom, and wear the elastic under your heel, pulling the pants down. Kindof like stirrups.
Or
2. You can buy what is called pre-wrap spray. It is a spray used to make your skin sticky to hold pre-wrap down, while the team trainer tapes over it. Pre-wrap is not sticky at all, that is why you use it under tape. The spray is sticky, but not as bad as tape. So, essentially you are gluing the pants, to your cleats.
Or
3. I don't recommend this. But, I have seen people cut 2 tiny holes in the front of their pants right above the bottom, then lace their cleats through the holes. You will have to cut the elastic heel so that the pants are more of bell-bottoms to do this.
Of course, pants that fit is best. You won't need to do any of those 3 options.