And whilst the Spanish coach is relishing some difficult team selections for Saturday's game at Swansea City, O'Brien is not one of them. It would be a major shock if he did not play.
Ever since he returned from a loan spell at Bradford City in 2018-19, O'Brien has been a key part of the team, linking defence and attack. Leeds United showed interest in him in the summer but were unable to agree a fee - what was offered is disputed by the two West Yorkshire clubs. But the speculation does not seem to have affected the 22-year-old, and this week he signed a new contract keeping him at the club until 2025.
Corberan believes it is how O'brien consistently competes that makes him special.
"It's fantastic news for the club because we know how important O'Brien is," he said. "He's an example of the players we have as a club. We want our academy players to have an impact on the first team.
"(Head of football operations) Leigh Bromby is very focused on the academy and we want to develop the young players because we know how important they are going to be for this club and to see how O'Brien works every single day, how he competes every time is very good.
"He can play well or he can play badly but it is very difficult to find a game where O'Brien doesn't compete well. Sometimes how you play can depend on the opponent, the shape, the structure, your team-mates, but how you compete is down to you.
"O'Brien is an academy player who is having a very big impact in the first team."
Aaron Rowe is still three or four weeks away from recovering from a fractured toe, Ryan Schofield still has a back problem, and Rolando Aarons is still building up his fitness after missing pre-season with a knee injury. Danny Grant's recovery is targeted towards joining the first team at Christmas.
Pipa and Jordan Rhodes remain longer-term absentees.
But every player who was available against Nottingham Forest last week has come through that game and/or the training sessions since unscathed, leaving Corberan with decisions to make as he decides how best to respond to the 2-0 defeat against a Swansea side who will try to play more expansively under Russell Martin.
"We completed a very good week for me because we had enough time to continue to develop the team," said Corberan. "Every player is available so I have to select the players to travel."