Reeco Hackett came off the bench to head a dramatic stoppage-time equaliser against Plymouth and ensure Pompey’s unbeaten League One record continued.
They created plenty of chances in an entertaining first half and deservedly took the lead through Josh Koroma’s excellent finish on his full debut.
But a Sean Raggett own-goal levelled the scores and substitute Niall Ennis soon struck to leave Fratton Park deflated.
It would have been an unfair outcome for the Blues, but after Brendan Galloway was dismissed for a second bookable offence, Hackett dramatically salvaged a point.
Danny Cowley made a single change from the side that won on the road at struggling Burton earlier in the week.
It came wide on the left, where loanee Koroma was handed his first start for the club in place of Ronan Curtis.
Everyone inside the ground paid their respects to Her late Majesty, Queen Elizabeth II before kick-off, with a minute’s silence followed by the national anthem.
When the action started, the tempo was high from the start and failed to slow down for the remainder of the first half.
Colby Bishop had a chance to grab an early goal, but was unable to keep his header down when Owen Dale picked him out.
Both sides were looking to get forward whenever possible, roared forward by two sets of fans who were contributing towards an excellent atmosphere.
And when Koroma’s pass was only cleared into the path of Tom Lowery, the midfielder’s dipping volley had to be saved by Mike Cooper.
Bishop was then fouled wide on the right and the free-kick from skipper Clark Robertson was deflected behind.
Dane Scarlett was next to go close, but saw his effort kept out by Cooper at point-blank range following some great combination play between Bishop and Koroma.
It looked as though Plymouth had broken the deadlock on 31 minutes, however, when Joe Edwards’ shot was diverted into the net by Finn Azaz.
But the flag was immediately raised for offside and the celebrations in the Milton End were abruptly cut short.
A moment of controversy soon followed at the other end of the pitch after a monster Marlon Pack throw had caused chaos in the Argyle area.
An overhead Raggett effort seemed to be blocked by the arm of Nigel Longwijk and still seemed to have just crossed the line.
The officials thought otherwise, though, and Pompey’s desperate appeals for either a goal or a penalty fell on deaf ears.
Pack immediately sent in another long throw that was flicked on by Bishop, but this time Raggett’s header was off target.
The hosts were forced to make a change on 40 minutes, with Lowery seemingly pointing to his hamstring as he made his way off the pitch to be replaced by Joe Morrell.
Pompey then made their intense pressure count, thanks to a moment of magic from KOROMA on the left.
He collected a pass from Robertson and while everyone was anticipating a cross, switched the ball onto his right foot and fired home a fine strike.
Both sides came close to adding to the scoring in stoppage-time, starting with a low Matt Butcher effort that had to be turned around the post by Griffiths.
Morrell then sent Scarlett racing clear at the other end of the pitch, only for Bali Mumba to get back and make a fine challenge.
And, from the resulting Robertson corner, a header from Michael Morrison flew into the arms of Cooper.
Half Time: Pompey 1 Plymouth 0
There was no let-up when the action restarted and the Blues were certainly not content to sit on their narrow advantage.
Koroma tried to add to his personal tally with a shot from a tight angle that flew into the side netting.
And there were more complaints from the hosts just past the hour mark, with the officials inexplicably unable to see Scarlett having his shirt tugged in the box by Dan Scarr.
Pompey’s displeasure at some of the decisions being made led to a yellow card being shown to Danny Cowley.
He soon made a double substitution to freshen things up, with Korma and Scarlett replaced by Curtis and Joe Pigott.
But the Pilgrms drew level in fortunate fashion on 74 minutes, when a cross by Mumba was inadvertently headed into his own net by Raggett.
And it soon got worse for Pompey, with Ennis racing onto Morgan Whittaker’s threaded pass and slotting the visitors in front.
Connor Ogilvie then had to clear off the line after Whittaker had beaten Griffiths to the ball and tried to find the net.
Pompey’s mood was not helped by referee James Bell’s reluctance to punish Plymouth for clear time-wasting.
Hackett was brought on for Dale, but it appeared as though time had run out for the frustrated home side.
The game roared back into life during stoppage-time, though, and the Pilgrims were reduced to 10 men.
Galloway was shown a second yellow card following a coming together with Morrison in the box and the visitors had to see out the closing stages with just 10 men.
But they were unable to do that and when Morrell sent a cross into the box, HACKETT deftly headed home the equaliser.
Pompey (4-4-2): Griffiths; Ogilvie, Morrison, Raggett, Robertson (c); Dale (Hackett 81), Pack, Lowery (Morrell 40), Koroma (Curtis 70); Scarlett (Pigott 70), Bishop
Goals: Koroma 41, Hackett 90+4
Booked: Pack, Hackett, Morrison
Subs not used: Oluwayemi, Swanson, Mingi
Plymouth (3-4-1-2): Cooper; Longwijk, Scarr, Gillesphey (Galloway 70); Edwards (c) (Cosgrove 66), Azaz, Houghton (Randell 66), Mumba; Butcher; Hardie (Ennis 56), Whittaker
Goals: Raggett 74 (og), Ennis 79
Sent off: Galloway (two yellow cards)
Booked: Azaz, Scarr, Cooper
Subs not used: Burton, Wilson, Jenkins Davies
Referee: James Bell
Attendance: 19,072 (1,899 away fans)