When the Warriors raced to a 28-6 half-time lead at Pepper Stadium on Saturday, the Panthers were booed off the field by their own fans.
Just 40 minutes later they had created history and saved their season.
It was one of those days.
The Panthers and Warriors set the season record for points in a game (64). The scoring frenzy lasted the whole 80 minutes. On a crazy and wildly entertaining Saturday night the Titans upset the Storm 38-36, combining for 74 points to kick-off a thrilling double-header in Brisbane.
By the time the Roosters had racked up 48 points against a listless Eels outfit on Sunday afternoon, Round 10 had become the highest-scoring round of NRL (400 points) since Round 25, 2015 (408).
It was Penrith's second biggest comeback in the club's history and the eighth biggest comeback the game has ever seen. It was also the biggest lead the Warriors have ever given up.
So what went so wrong for the Warriors and so right for the Panthers?
The Warriors scored five tries to one in the first half, despite having only 44 per cent of the ball. Their average play-the-ball speed was more than half a second slower than their opponents and they had made 15 ineffective tackles to seven. The Panthers were left to rue 16 missed tackles in the first half.
The Warriors took full advantage of a 12-man Penrith outfit - after Waqa Blake had conceded the most blatant of professional fouls in the 11th minute to be sent to the sin bin - racing in two tries and then seemingly putting the game to bed on the stoke of half-time with a length-of-the-field intercept.
While they racked up a big first half lead, the Warriors had only managed an extra five play-the-balls (15-10) inside the Panthers' 20-metre zone at the break.
Still, a 22-point lead should have been more than enough for a Warriors team looking to make it three wins on the trot with a place in the top eight on the line.
But then the siren sounded for half-time and the game completely changed.
In the next 40 minutes the Panthers ran for an incredible 720 more metres (1,145 to 425) than their shell-shocked opposition. They completed 23/24 sets at 96 per cent, forcing the Warriors to make 196 tackles in the second half, including 25 missed tackles (below).
Once the Panthers seized momentum they simply refused to let it go, racing in four tries in a 12-minute window and earning 23 play-the-balls in the Warriors 20 metre zone to zero.
But most alarmingly, the Warriors managed just five play-the-balls in the Panthers half in the entire 40 minutes, including a 19-minute stretch where they never got over the halfway line with the ball.
In fact it took 30 minutes of the second half until the Warriors got consecutive play-the-balls over the halfway line and it only happened once, such was the total domination from the Penrith side.
No wonder the Panthers were able to score 30 unanswered points.
"It takes a tough team to come off the canvas like that. We knew we had that in us and we were talking about winning the game at half-time and not giving up," Panthers coach Anthony Griffin said after the game.
Warriors play-the-balls in Penrith's half in the second 40 minutes:
42nd min: play the ball on tackle five, just inside the Panthers' half.
52nd min: play the ball on tackle five just over halfway.
71st min: two plays over the halfway line - their only consecutive plays in the entire half.
76th min: final play in opposition half.
Newcastle Knights rewarded for effort
The Knights recorded just their second win of the season when they upset the Raiders on Mother's Day, but it had been a long time coming.
The Newcastle outfit have hit the lead in seven of their 10 matches this season but have lacked the belief, experience or the ability to own the big moments when it has mattered most.
They led the Warriors in Round 1 with just seven minutes left, they led the Rabbitohs at half-time in Round 3, and in Round 5 the scores were level at 18-18 with just seven minutes left against the reigning premiers before a James Maloney field goal broke their hearts.
In three of their last four games the Knights led at half-time against the Bulldogs, Cowboys and Titans before going down in each game.
But against the Raiders, the Knights refused to go away and out-enthused their more fancied rivals in the final 30 minutes to run away with the contest sparking emotional scenes in the Hunter.
It was the club's biggest win in 629 days, and for forward Josh King, it was his first victory in 14 attempts in the NRL.
Short drop-out is the odds-on play
The Bulldogs' short drop-out tactic has divided opinion and surprised many commentators, but coach Des Hasler is onto a winner and the statistics prove it.
The Bulldogs have had 18 dropouts this season and got the ball back seven times, at a strike rate of 38.8 per cent. Not bad when every other team gives the ball back 100 per cent of the time.
The added benefit for the Bulldogs is that when they don't get the ball back, their defence is not working any harder than it absolutely has to. There is no running out 50 metres and then retreating as the set goes on. They are able to stand on their line and rush out.
NRL teams are more than happy to give away multiple penalties on their own line and the only difference with this tactic is that it gives them a chance to get the ball back.
The modern game has evolved, and it's only a matter of when, not if, other coaches adopt the tactic. Once it catches on, we'll wonder why the long drop-out ever existed, like kicking duels.
Napa's great gesture
He was rocked in the first half by a massive Nathan Brown tackle, but the biggest hit of the night came at full-time when Roosters forward Dylan Napa gave away his jersey to a young fan in the crowd.