Well, considering Conor has a full 7 inch reach advantage over Pacquiao, and Pacquiao was still able to land that straight left, Conor should be able to land one too, and maybe even have an easier time landing it. Considering Conor is (most likely) much stronger than Pacman and wont be fighting with a bum shoulder, if he lands a big one, at the very least it should stun Floyd. Maybe even long enough for Conor to follow up with 1-2 more big shots.
If he can overcome Floyd's speed, we may have a fight on our hands.