The news hardly came as a surprise even if its timing, just a day before Ulster return to action, did throw us all a bit of a curveball.
Indeed, whispers of Johann Muller's retirement at the end of the season had been doing the rounds since before Christmas, it was just that the man himself kept reassuring those who asked that his final decision would be made early in the New Year.
He then set a deadline in the run-up to Ulster's last two pool rounds of Heineken Cup action and made it known that after the break, following the Welford Road game, there would be clarity after he had sat down with his wife and talked things through back at their Mossel Bay home in South Africa's southern Cape.
So, the 33-year-old World Cup winner's decision to presumably return to the family farm – where he has already built a 'retirement' house – had already been pretty well flagged up and with no sign of his contract being extended, it all seemed inevitable really.
And now not only must Ulster replace their inspirational leader – though Rory Best looks a pretty good fit for another crack – but with John Afoa and Tom Court departing to play in England, three key forwards are now leaving and leaving considerable voids behind them.
Of course, squads must evolve but Ulster will now have to somehow maintain the excellence in preparation that Muller has demanded of them since he touched down here in summer 2010.
Though his regular game-time was diminishing due to the more regular onset of injury, there has still been no doubting the Ulster skipper's presence and what he brought to the table in terms of his organisation skills and leadership.
That was clear to see in last month's victory at Welford Road. Even though he was out on his feet at the end and really ought to have been trying to recover, the former Springbok gathered the Ulster squad around him in a tight circle and somehow got the oxygen back into his lungs to deliver a speech over what had just unfolded.
Though he has always maintained that there is little that needs to be done when having to lead this Ulster side, Muller's influence has been seminal in the squad's growth during his time here.
Four years ago he accepted David Humphreys' offer to come over and set about bringing belief and direction to pretty much every aspect of the squad's preparation.
It has been said that he is a de facto forwards coach and certainly Muller's main area of expertise was to give his new side an attacking and defensive lineout that would be the envy of others.
Always a hard grafter, Muller's strengths lay in his captaincy and workrate around the pitch. The former Sharks player also inspired those around him and his qualities as a player raised the bar for all the players around Ravenhill.
His friendship with Ruan Pienaar undoubtedly played a pivotal role in Ulster not only landing a world class scrum half but also in helping to settle both couples into life here, with the families living beside each other in east Belfast.
They could have closed the gates behind them with Muller and Pienaar simply playing rugby and pocketing generous wages but, again, that was never the plan and Muller's intention was always to buy into living here which he and Pienaar have done with notable results especially through their faith.
Humble away from rugby, on the field, Muller's impact cannot be underestimated. It brought results too and gave Ulster a greater steel to what could be achieved. In his debut season here, Ulster made their first Heineken Cup quarter-final since way back in that much-fabled 1998-99 season and the squad have done so every season since. That has not been coincidental.
Nor indeed was making it to last season's PRO12 final while also showing that the side can win competitively in France.
The only downside to it all has been a distinct lack of silverware. Though Muller is adamant that Ulster will get there soon, he would dearly like to depart with a winning medal in his pocket and not just the two losing ones picked up from 2012's Heineken Cup final and last season's PRO12 showdown.
Yes, Muller's commitment to here has been total. Though there will be no let up in his commitment to Ulster over the next few months, which will hopefully stay injury free, his loss to the province comes at a critical time, both in the squad's evolution and in his own acceptance that it all just has to stop.
As he said yesterday: "I just feel from my body's point of view that the time is right to step away.
"But there is still a lot of rugby to be played. Nothing has changed for me," he added just in case you thought he was packing in early.
Hopefully, Muller will bow out with that well-earned winning medal. There could hardly be a more fitting reward for what he has brought to Ravenhill.