Tom Naylor was left with mixed feelings after Pompey departed Home Park with a point.
On the one hand, they trailed at the break against the holders of the best home record in League One.
But the skipper’s strike, which came a couple of minutes after John Marquis had levelled from the spot, looked like it might seal victory against Plymouth.
So Naylor was disappointed that the Blues conceded a poor equaliser to stop them climbing to third in the table.
The midfielder said: “Plymouth have been excellent at home all season and it’s clearly a hard place to come, so it’s a good point in that sense.
“We edged it in the second half – and were a lot better than we were in the first – but conceded two sloppy goals.
"We improved and went 2-1 up after the break and we needed to see it through, but unfortunately we couldn’t."
“That’s something we could all agree on in the changing room and we need to concentrate a lot more to cut out those mistakes.
“Our passing wasn’t the best in the first half and we gave the ball away on a lot of occasions. We tried to get it to the front four a bit earlier than we should, instead of taking that extra pass.
“Then we improved and went 2-1 up after the break and we needed to see it through, but unfortunately we couldn’t.
“If you take away our first couple of games this season, then we’re right up there. The confidence is high and we’ve been brilliant over the past few weeks.”
Naylor found the target for the second time in as many appearances with a crisp effort that left Michael Cooper helpless.
He said: “It was a decent one, to be fair. I had a strike just before then and the keeper made a great save from that.
“So I was feeling confident when the ball fell to me again and it’s always nice to see it fly in the bottom corner.”