The Spanish coach has selected his compatriot in goal over the past few weeks and benched Aaron Ramsdale, to the chagrin of some Arsenal fans.
Raya was caught out by Mykhailo Mudryk's looping cross which flew into the net during the 2-2 Premier League draw with Chelsea on Saturday, later making another mistake which the Blues did not capitalise on.
"Errors are part of football, mistakes happen from defenders, strikers and goalkeepers," Arteta told a news conference Monday in Seville.
The coach said he did not think Raya was suffering in the spotlight, with some Arsenal fans chanting Ramsdale's name during the draw which saw champions Manchester City move level on points with the Gunners at the top of the Premier League.
"I haven't seen that (he's suffering), I haven't seen that at all," said Arteta, who previously suggested he might rotate the two goalkeepers but has only used Raya since handing him his debut in September.
"That's the pressure of playing for big clubs where you have to win and you have to be at your best and you have someone next to you that is pushing you every single day.
"That's the debate and the beauty of the game as well and the fact that you have other options are going to make all that talk more frequent."
Arteta confirmed Ramsdale was available and in the squad to face Sevilla after he missed the Chelsea match for the birth of his son.
After a disappointing 2-1 defeat at Lens, second-placed Arsenal are looking to get back on track in Group B.
Sevilla have proven a force at home in European competition, beating Manchester United and Juventus at the Ramon Sanchez-Pizjuan on their way to a record-extending seventh Europa League title last season.
Arsenal midfielder Jorginho said the team would need to keep their emotions in check on what was sure to be a fiery night.
"For sure they're gonna be ready for us, and the atmosphere here is going to be hot," the Italian told reporters.
"I think it's going to be a great game and a good test for us as well, about emotional control."
