This may sound crazy but I'd pair Infernape with Mega Slowbro. Type wise they fit perfectly defensively and offensively. You have two insanely different Speed Tiers and you have a Special Attacker to defeat Pokemon from both defensive sides. You don't even need to mega evolve it if you don't want to, so you could run an extra mega Pokemon if/when you play Battle Spot.
Slowbro @ Slowbronite
EVs: 252 HP / 36 Def / 136 SpA / 80 SpD / 4 Spe
IVs: 0 Atk
- Slack Off
- Grass Knot