At 29, he finds himself at a career crossroads. His contract expires in June but an extension would appear unlikely, and it is doubtful whether Stewart would sign one in any case.
Not only was he anonymous before being substituted at half-time against Motherwell, he was also denied the skipper's armband after returning from a calf injury. Manager Jim Jefferies continued with Marius Zaliukas as on-field leader for what was a critical league fixture in the context of the club's European ambitions. That move would have found favour in Lithuania, where majority shareholder Vladimir Romanov is known to harbour serious disdain for out-of-contract players who aren't falling over themselves to sign an extension.
To all and sundry, it appears Stewart's days at Hearts are numbered and supporters do not seem overly distressed about losing their captain.
The cheering around Tynecastle when stadium announcer Scott Wilson revealed the midfielder would not be re-appearing for Saturday's second half illustrated the public dissatisfaction. It would also have been like a knife through the player's heart.
His performance was sub-standard, something even he could not deny. But Stewart was not the only figure in maroon to fall below expectations.
It should be remembered he was starting his first game since February and could in no way be considered match fit. Motivation may also have been affected by the pre-match decision to leave the armband with Zaliukas, although Jefferies did not consider that a major problem.
"Michael was made captain here by the previous manager," he explained. "It does not matter if he's been captain here before, I'm in charge here now and I'm looking at things differently.
"Marius has come in while Michael was out. I just left it as it was. Michael's been out of the side and he trained well last week. I said to him just to go out and concentrate on the football and Marius will continue to be (captain].
"I don't think that's a big issue. Marius has captained us before, it's not something that should bother anyone."
What will strike a chord is the collective opinion of the Hearts support.
Sitting in the home dressing room during the interval on Saturday, Stewart could not have missed the sound of fans hurrahing his substitution.
"Michael's an experienced player. He knows himself he didn't play well," continued Jefferies. "I'd expect him to know he didn't play well. Maybe he's tried to get back and he's maybe feeling the injury a wee bit. I don't know. I can only go by what I saw on the pitch.
"If I could have put six substitutes on I'd have done so at half-time. I wanted to put three on. David Obua complained of feeling his back but we only made two subs and let him continue for 15 minutes. If I could have put all six on I would have because the first half wasn't acceptable.
"You give players the opportunity and they go out there but they were well beaten. Motherwell wanted to win the game more than we did.
"It wasn't just the midfield part of it. When the ball was up front we didn't hold it, we didn't battle with their defenders to keep anything. We snatched at chances.
"Ruben Palazuelos had a decent game, Ryan Stevenson did well in a different position but the main one for me was Lee Wallace. He kept his form up and was outstanding."
While Wallace's recent imperious displays may attract the attention of English suitors this summer, Stewart becomes a free agent in a matter of weeks.
Indications of where his future will lie are decidedly absent. He has never been one for becoming flustered over contracts and is content to bide his time and weigh up whichever options present themselves.
He could be attracted by an opportunity to sample continental football, having played almost his entire career in the United Kingdom.
Born in Edinburgh, he was lured to Manchester United as a teenager, where he sampled the intensity of Champions League ties at venues like La Coruna's Estadio Riazor in Spain.
A six-month loan spell with Belgium's Royal Antwerp is the sum of his European adventures and he may be swayed by any chance to move abroad and already has close connections with agents in Germany.
Stewart's reputation in Edinburgh is of a supremely gifted footballer who, at times, was difficult to manage. His public fallout with John Collins at Hibernian precipitated his departure from Easter Road, while on-field indiscipline often compromised his effectiveness at Hearts.
There is no denying his talent, his enthusiasm, his drive and tenacity. In fact, Stewart possesses all the attributes to be one of the finest Scottish midfielders of the modern era and it could be considered something of an injustice that he only holds four international caps. Temperament remains questionable, so his next move should reveal much about how his career will pan out.
At Hearts, he found something of a soul-mate in Csaba Laszlo, the eccentric Hungarian coach who understood Stewart and how to motivate him. In fact, the player's most consistent spell of football to date came during Laszlo's 18-month tenure and contributed to his appointment as club captain last summer when Robbie Neilson defected to Leicester City.
"I made Michael the captain because he was the club's most consistent player and he was the best goalscorer from midfield," said Laszlo. "His attitude was good and he was a good leader. I think he was a good player for Hearts. Now he must decide his future but this is his decision."
Laszlo implored Romanov to re-sign Stewart shortly before losing his job to Jefferies. The player then held discussions with the Hearts hierarchy and Romanov personally. Having done all the pre-ambling there is no final outcome with less than two weeks of the season remaining.
It seems Michael Stewart's Hearts career is winding down. But where will his next move take him?