Howe admits they couldn't get the striker in the game over the day.
Howe told Chronicle Live: "We shuffled it around a little bit today to find (a solution.) I don't think we were great starters; we conceded a goal.
"We needed fresh impetus with the starters, especially in the second half; it was our best period in the game.
"In the end, Nick, we struggled to get him into the game with the amount of balls we would have liked. Even when we moved him to centre-forward he was short of touches and short of goalmouth involvement.
"That's why we made the changes."
Asked if they're hopes to European qualification is slipping away, Howe continued: "Certainly with relation to the Premier League. Our form for a while has not been strong enough, not been good enough.
"We know that and take responsibility for that. It is really frustrating for us and that is the perils of Europe. We have tried to be laser-focused on every game. We have given every attention to every game with the same importance.
"But with a deluge of games, your focus can be swayed. Our Premier League return in recent weeks has been nowhere near the level it has been historically.
"Our home form has been so reliable (historically), but it has tailed off, and we have to grab that back as quickly as possible. When we are playing here, we want this to be the place where we pick up the most points and a place where players feel free to play and through our own performances, that hasn't been the case."
Howe also took off Anthony Gordon, which was greeted by jeers from the home support, though he added: "I genuinely wasn't aware of that. I think in every moment where that is the case, we have got to try to stick together. I will certainly back him and hope the supporters do."