The suggestion in some quarters was that Aberdeen had not been truly tested during their opening 12-game winning streak this season.
But Sunday’s 3-2 win over Hearts showed what Jimmy Thelin’s side are made of.
After Blair Spittal put the visitors ahead in the second half, Aberdeen trailed for the first time this league season.
Their reaction was to level within two minutes before going on to score an 88th-minute winner after their opponents went down to 10 men.
That made it 13 wins from 13 games for Thelin since his arrival in the summer, with the club record of 15 consecutive wins now in sight.
But with Celtic in Glasgow up next, can they really keep that run going?
‘The more you win, the more you believe’
To say Aberdeen have not really been challenged in this run is over-simplistic and downright wrong, but it is true to say they are yet to face either of the Old Firm.
Celtic are flying similarly high domestically and only sit above the Dons on goal difference – a difference of 13 goals, right enough.
Brendan Rodgers’ side will be huge hurdle to clear, but the manner of victory over Hearts should give Aberdeen even more confidence, according to former St Johnstone boss Craig Levein.
“The more it happens, the more you believe,” he said on Sportsound. “Things didn’t go their way, and if there was any self-doubt, they wouldn’t have come back.
“They’re carrying a little bit of good fortune, but they’ve won and come from behind. They can only be talking positively in the dressing room.
“If you score late winners, it makes it even better the next time you take the field because there is more evidence behind you that you can be victorious.”
Aberdeen were second-best for large spells against Hearts but after Jorge Grant’s red card for a second yellow, the tide turned and a buoyant Pittodrie crowd – and some smart substitutions from Thelin – helped earn them victory.
“What made the difference for me was the firepower they brought off the bench,” Levein added. “Their back line is good, their goalkeeper is good and they have attacking options.
“The fans are fully behind this team, you could sense that from the start. Pittodrie was bouncing.
“There’s enough evidence with the results to date to make Jimmy Thelin think he can go to Celtic and have a go.”
‘Big fixture at Celtic Park is now a huge game’
Although we now have to wait two weeks for the top-of-the-table game, the fixture will receive far more build-up than it usually has done in recent years.
“Two teams, seven straight wins, 21 points each – it sets it up perfectly,” former Aberdeen forward Billy Dodds said on Sportsound.
“It’s a big fixture anyway but it’s a huge game now. There’s so much to lose, a lot to gain as well. We’re all looking forward to it.
“It’ll be so talked about, the build up to it, it’s one that stands out for the first time in a long time.”
The bad news for Aberdeen fans is, unsurprisingly, you have to look pretty far back for the last time they won against Celtic.
The most recent was in Glasgow in May 2018, when an Andy Considine goal was enough to win on the final day of the season and secure a second-placed finish in the Premiership.
That is a run of 25 games unbeaten for Celtic, in which 20 of those were victories. For one run to continue, another must end.