The collision happened early Friday, when the Legend drifted into the Glory while docking in Cozumel.
Some damage was visible on the front of the Legend when it docked early Sunday, according to reports.
The damage to the Glory appears to be more extensive.
Video by eyewitnesses at the scene showed the bow of the Legend hitting a rear observation deck of the Glory, sending debris into the water below.
Inside the Glory, panic ensued.
Passengers and crew who were inside decks 3 and 4 scrambled to get away as the Legend's bow sliced through a dining area.
“The bow of our ship went straight through the dining room. And they say it was mass chaos," passenger McKenna Morris told Tampa station Bay News 9. "And even some of the workers in the dining room were running over people trying to get out because no one had seen anything like this happen before."
The collision left a large gash and structural damage to one side of Glory's stern.
Carnival representatives later reported six guests had suffered minor injuries during the crash and required some medical attention.
Later in the day, Carnival Cruise Lines apologized for the crash in a letter sent to guests.
"The bow of our ship went straight through the dining room. And they say it was mass chaos." — passenger McKenna Morris
The captain of the Glory said a preliminary investigation showed the crash was due to “spontaneous wind gusts and strong currents.”
In another statement issued after the crash, the cruise line said, “Carnival Glory was maneuvering to dock when it made contact with Carnival Legend which was already alongside. We are assessing the damage but there are no issues that impact the seaworthiness of either ship,” Carnival said in a statement. “We have advised guests from both ships to enjoy their day ashore in Cozumel."