He shook hands with the man who’d been his boss last season, he did the same with the match officials, he walked right across the pitch to salute the huddle of hardy Rotherham United souls who’d made the four-hour journey to South Wales.
There was nothing for the players he has taken every chance to praise in his bid to lift spirits during his time in caretaker charge of the Millers.
Paul Warne, head bowed as he trooped down the tunnel, was entitled to feel let down.
The Championship basement club’s surrender, once the second goal went in on the stroke of half-time, was as meek as in the 4-0 derby drubbing at Barnsley back in August in the days of Alan Stubbs.
They were hit by injuries, robbed of key loan men unable to play against their parent club, but there can be no excuses for such a failure to compete.
The performance, as bad as anything so far in a season of woe, embarrassed a good man who deserved better.
“At times, it looked like men against boys,” Warne lamented.
“To come here and take such a ‘drumming’ is a bit of a wakener for some of my players. If they want to play at this level, they need to up their game.”
It didn’t help that the home crowd were singing the name of Neil Warnock, the Cardiff City manager who engineered last season’s Millers survival miracle when Warne was fitness coach.
There will be no great escape this year. After this supine show, Rotherham are 15 points adrift of safety with only 13 matches remaining.
Warne, since taking the reins in November, has done enough in near-impossible circumstances to make himself a candidate to lead the club when they find themselves in League One.
After this, who knows whether he’d want to.
In the second half, when the humiliation was at its height, he stood in stony-faced hurt in his technical area, kicking out at the air in disgust.
The most positive figure in the Millers camp suddenly looked very alone.
Err, there wasn’t one.
The centre-forward with the long contract and big wages was handed a first start since January 7 in the absence of top scorer Danny Ward with a calf problem.
In a scenario now becoming depressingly familiar, he asked virtually no questions of the opposition backline and found himself back on the sidelines before an hour was up.
He was dominated by Sol Bamba, but shouldn’t be made a scapegoat on a day when so many other Millers also failed to deliver.
Ward and Lee Frecklington (both injured) Tom Adeyemi and Semi Ajayi (both ineligible) were out of action for reasons not of their making.
They weren’t the only ones to go missing at Cardiff City Stadium.
The game was gone by the interval. Nine minutes later, it had become a rout.
The Millers fell behind to the first chance of the encounter, Kadeem Harris curling his 11th-minute shot beyond goalkeeper Richard O’Donnell’s left hand, and on the stroke of half-time Junior Hoilett latched on to Ben Purrington’s errant back-pass to slot home.
It signalled the end of the contest and the beginning of the embarrassment.
Four minutes into the second half, after Rotherham new boy Joel Ekstrand marred his debut by gifting Cardiff possession with a misplaced pass, Craig Noone volleyed in from the right and, five minutes later, Kenneth Zohore finished emphatically from a tight angle on the opposite flank.
What Rotherham lacked in quality, they didn’t make up for in anything else, and they were found wanting in character and application as the home side applied the pressure.
A lovely 83rd-minute minute lob on the run from Zohore confirmed the heaviest of the Millers’ 16 defeats in 17 away matches this term.
“No-one goes out to play badly. But, collectively, not many of my players manned up,” Warne said.
“We didn’t create a great deal. Cardiff had, let’s be honest, much better quality throughout their team, a lot more pace and power. We couldn’t deal with that.”
For those of a squeamish nature, look away now ... the Millers have conceded 73 goals in 33 league games this season and their goal difference is -43.
Warne, to his credit, has kept a Rotherham team not good enough for the second tier competitive since stepping into the hot-seat.
Only in the second halves of January losses at Leeds United and Newcastle United have Rotherham been comprehensively taken apart.
Until the calamity of Cardiff.
The interim boss confessed that he just wanted the nightmare to be over as the goal tally mounted in the second half.
“It wasn’t about blowing the minutes down, I was blowing the seconds down because I knew then the game had gone,” he said.
“Joe Newell, in the last 15 minutes, couldn’t move. His ‘glute’ tightened up, so we were virtually down to 10 men as I’d made my three subs. It was then all about the final whistle. I hate to admit that, but that’s the truth.”
Rotherham’s sense of shame grew deeper in the 56th minute when Jon Taylor shot well over, a first proper attempt by the Millers which drew mocking cheers from the Cardiff fans.
Bluebirds supporters repeated the sarcasm not long after when a cross from Anthony Forde bounced harmlessly into the Cardiff box and into the arms of keeper Allan McGregor.
We’ll never know how they would have reacted to a meaningful Millers effort on target.
There wasn’t one.