Manager Thomas Frank, whose side have drifted into the relegation battle in Toney's absence said it was a massive boost to have him back, for his goals and his leadership.
"He's bossing. He's like an eight-year-old boy, he just wants to go out and play," Frank told a news conference on Friday. "Just that pure joy of playing football.
"I'm looking into the eyes of a player who is very committed, very excited. He will start tomorrow, he will lead the team out, he'll be the captain. I'm sure he'll be ready."
Toney scored 20 goals in 30 league appearances last season but was banned for betting offences.
The return of the man his Brentford teammates refer to as 'Big Dog' could not come at a better time with the club in 16th place, three points above the relegation zone, and one point behind 15th-placed Forest.
"Not only this week, the last three-and-a-half years, he is a special character in many ways, he's a fantastic person to be around myself, the staff, the players, the energy he brings, the smile, the positivity at the training ground," Frank said.
"On the pitch, he wants to win, he wants to help the team, of course it's a massive boost. It's like a new signing. He's the second-best striker in my opinion in the Premier League."
One worry for Frank is that with the January transfer window still open, Toney could be lured away by a big-money offer from a Premier League rival, although none have arrived so far.
"As I said earlier in these conferences, it's 99% something, that he will stay here but football is crazy, you never know what will happen tomorrow," Frank said.
"He's committed to helping the team, that's all that's on his mind he wants to stay here, he wants to help the team."
