The boss is not looking forward to telling any players they will miss out on the big occasion but appreciates it is a squad game, and everybody has played their part. The substitutes could, of course, end up having a huge impact in the 20:00 BST kick-off.
"I like the responsibility," he added. "It's my job and I'm quite comfortable with that. My job is to help the rest of the staff to cope with the excitement of the final, especially the players.
"Of course, it's not a good thing for any player to hear that [being left out] but I'm quite comfortable with that, it's my job.
"I think the problem we have in some games this season, we had a lot of players out from injury. So it doesn't matter if you play one minute in the final. Of course, you want to play 90 minutes but the important thing is to win. If we win, all the players are going to win this final and they all played in the Europa League, so that is the most important thing."
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MUTV will provide unrivalled build-up to the blockbuster occasion, starting with live training on Tuesday morning (11:00 BST) before the squad travels to Bilbao. You can watch analysis from the San Mames that evening, plus Ruben's press conference, which will be conducted alongside two players. On matchday itself, we have four exclusive broadcasts from the city at 09:00, 12:00, 16:00 and 18:00 BST. Subscribe now to tune in, with live radio commentary of the game to follow, plus full match replays from midnight.