Phillips netted his first goal for the club as Pep Guardiola's side managed a 3-2 victory over Red Star Belgrade on Wednesday night.
Youngsters Micah Hamilton and Oscar Bobb also netted on the night, prior to Phillips' penalty five minutes from time.
The 28-year-old made just his second start for the Sky Blues as he helped his side maintain their 100 per cent record in the Champions League this term.
Phillips' muted celebration after converting his penalty seemed to reflect his position within the squad.
He could be seen waving and blowing kisses to the travelling Man City fans inside the stadium after Phil Foden allowed his teammate to take the spot kick.
read more on manchester city
Liam Gallagher is every Man City fan as he sends message to Micah Hamilton
Heartwarming moment Pep Guardiola realises he first met Micah Hamilton as a ball boy
It prompted suggestions that the former Leeds midfielder could have been hinting that he is leaving the club this winter.
Grealish later took to Instagram, sharing a post from Man City's feed showing Phillips' reaction, tagging the player, and adding three blue hearts.
Haaland, who is currently out injured, watched the game at home and also posted a picture of Phillips with a heart emoji.
"He's an incredibly good taker," Guardiola said post-match lavishing praise on Phillips.
Most read in Champions League
Liam Gallagher is every Man City fan as he sends message to Micah Hamilton
Heartwarming moment Pep Guardiola realises he first met Micah Hamilton as a ball boy
Howe hints at more injury woe for Magpies as key duo pick up knocks in defeat to AC Milan
Howe takes positive in Newcastle sticking to values as Ferdinand points to plus in defeat
"I know Phil [Foden] had ambitions to do it but Kalvin is an incredible penalty taker.
"The game was not over and for his confidence... it was a difficult game because they made man-to-man so aggressive, a lot of interruptions and so many fouls. it was not easy to play comfortably but in the right moments we found our quality."
Phillips has recently been linked with a move to Newcastle, Manchester United, and Juventus.
The Leeds-born midfielder is seeking regular game time as he eyes a place in Gareth Southgate's squad for next summer's European Championships in Germany.
Kalvin Phillips opens up on his lack of game time at Manchester City in his England post-match interview