Loftus-Cheek, 22, has played just 33 Premier League minutes this season – and he has started only two games in all competitions.
He is below four other midfielders in the pecking order but took a rare chance to impress by smashing in a hat-trick against Bate Borisov.
The England man took the match ball afterwards and held it under his arm during interviews.
Loftus-Cheek’s Chelsea team-mates had signed it with messages such as ‘congrats brother’ and ‘top mate’ seen written on it.
But there was one slightly bizarre comment referring to a sex toy penned by one unknown Chelsea star which read ‘Yes Rubs, rampant rabbitt!’.
It is unclear who wrote the message.
Maurizio Sarri hailed Loftus-Cheek and revealed he hadn’t been playing this season due to a need to improve defensivel.
“We have four midfielders and three of them have the same characteristics,” Sarri told BT Sport.
'You can have one, you can have one, you can have one'
Ruben Loftus-Cheek handing out #UEL goals like: pic.twitter.com/CQfgPyPnF2
— Goal (@goal) October 25, 2018
“They are offensive midfielders, only one has other characteristics – [N’Golo] Kante is a defensive midfielder. So it is very difficult to put in the starting XI two midfielders with the same characteristics.
“We have a tactical problem with the midfielders.
https://twitter.com/VintageEden/status/1055553696891854848
“At the beginning of the season he [Loftus-Cheek] was a very good player and now he is a good player that is more suited to my style of football.”
While former boss Glenn Hoddle says the hat-trick hero needs to quit Chelsea to become an international star.
Hoddle said: “Some of the stuff Ruben has done is delightful. I just fear for the lad … he’s got to move if he wants to progress.
“He’s an England talent and we want to see him playing. I want to see if he can take these performances on to the pitch against the bigger sides.
“Put him up against a Man City or a Liverpool and see what he can do.
“Nobody knows if he can play three games in a row he doesn’t know.”