The 25-year-old joined the Scottish Premiership champions from Dundee United midway through last season.
The 25-year-old moved to the Scottish Premiership champions from Dundee United midway through the last campaign. And while he endured a slow start to his first full season, he has begun to show the form that persuaded Ronny Deila to bring him to the club in the first place, scoring four goals in his last six games including a brace in the 3-1 win over St Johnstone last month.
And Mackay-Steven has offered an explanation as to why he has enjoyed a much better run of form lately.
"The training is at a high tempo here so you become really fit," he told STV.
"The manager wants the wide men to contribute going forward and back so that’s what I've tried to do.
"I've improved defensively since I've come here, and tactically. That’s something we do a lot of work on in training so that side of things have been beneficial for me."
It is hardly surprising that the Scotland international has now begun to prove exactly what he is capable of. The emphatic 8-1 victory over Hamilton in January was the first game that the midfielder had started since the club's Europa League tie with Ajax almost two months previously.
And while the Hoops have endured a couple of disappointing results since Mackay-Steven returned to the starting line-up, his own form during his run in the team should give Deila plenty of confidence that he can remain a valuable member of the side as they look to wrap up the league title.