But he then saw a rare appearance for the Blues cut short, just as he was getting into his stride.
The on-loan [Albion](https://www.theargus.co.uk/sport/albion/?ref=au) attacking midfielder made his first appearance for six weeks as he started the Carabao Cup quarter-final at Cardiff City.
He remained in the XI amid half-time changes after the Premier League outfit had struggled in a goalless first period.
Buonanotte, who had looked rusty to that point and was maybe lucky to stay on, then got into his stride, helped by having the outlet of substitute Alejandro Garnacho wide on the left.
The duo combined for the opening goal and Buonanotte went close himself as he looked to be asserting some influence on proceedings.
And then, on 66 minutes, Chelsea boss Enzo Maresca took him off.
Cardiff drew level but a deflected late strike by Pedro Neto and Garnacho’s second, right on time, completed a 3-1 Chelsea win.
Buonanotte had not played since a 19-minute outing against Qarabag in the Champions League on November 5.
That lack of playing time might have been a factor in him being removed from the action, especially when Chelsea seemed to have the tie under control.
But it was frustrating timing for those hoping to see the Argentinian run through his range of play-making skills.
Recent evidence suggests Chelsea would not have been saving his legs for Premier League action.
Maresca said his side were good without the ball even in the first half.
He added: "Facu is not playing a lot. So we expect some difficulty in the first half, and then in the second half, with the change, we were quite better.”
The League One leaders had been causing Chelsea plenty of concern until Buonanotte picked off a pass early in the second half, made ground and timed his pass perfectly for Garnacho to open the scoring.
The compatriots posed on a wall in front of the away fans as team-mate Joao Pedro pretended to take a photo.
Buonanotte later unleashed a trademark left-foot curler cutting in from the right which was fingertipped over the bar.
His continuation, or otherwise, at Stamford Bridge when the January transfer window opens was raised at a recent Fabian Hurzeler press conference.
The Albion head coach said: “Let's see when January comes as to how we try to make the team better and what changes we want to do. But now we still have a few weeks to go.”
Albion appear to have plenty of options in areas where Buonanotte operates.