Error: Lionel is nigh killed by Gawaine on two subsequent days!

Correction: I checked from Malory, and this is a duplication error. Lionel lances against Gawaine on the first day and is impaled by Gawaine's lance. He does not appear on the second day at all, which makes sense, having been almost mortally wounded the previous day.

Omission, 2nd day: Bors unhorses Gawaine as well on the second day as they fight one another individually. Both Gawaine and Bors are badly wounded, and unable to continue fighting. (GPC mentions no damage and just has Gawaine unhorsing Bors, which implies that Gawaine is hale and hearty.)