"I know about it since yesterday. I'm here to be in the toughest competitions, that's why I'm at Chelsea," Tuchel told a news conference ahead of Tuesday's Premier League encounter with Brighton & Hove Albion.
"I was clearly not involved and my players were not involved in the decision-making process. My role is to be coach, to be focused and we have an important game coming up tomorrow."
Abraham, 23, is Chelsea's top scorer this season with 12 goals in all competitions, but has found himself marginalised since the arrival of German coach Tuchel in January.
"I cannot make a decision on the personal goals of players," Tuchel told a news conference ahead of Saturday's Premier League game at Crystal Palace.
