I think him missing the OF is a blessing in disguise.
I know hes not been involved in so many flare-ups during these games as before but you know they will do anything and everything to try and win this game by skulduggery and the refereeing is so poor Morelos could easily pick up 2 bookings during 90 mins.
You can see in most games any challenge, even, often especially, the nothing ones, opposition players are throwing their arms up in the air or shouting at him all the time trying to draw a reaction and convince the referee Morelos is up to something. If the game is going badly for Rangers or him, the chances of a reaction are exponentially increased and we cannot afford to lose a man in a game like this.
Hes a really good player and hes had their number recently but this is a Golden Opportunity for Rangers to win the game and effectively kill their title bid. We may miss his goal threat but I think having his temper on the shelf is more of a boost just this once and Rangers have the players to win the game without him.