League One Bradford twice led Championship side Millwall in the pair’s FA Cup Third Round tie, before Ricardo Fuller’s 83rd-minute equaliser levelled the game at 3-3 and forced a replay at Valley Parade on 14 January.
But Parkinson said despite letting the advantage slip, his side can take heart from their performance.
Millwall 3-3 Bradford City
FA Cup Third Round Proper
Saturday 3 January
The Den
“It was a test for us today and we set out to see how we’d look against a Championship team,” he said.
“We’ve beaten Leeds at home and it was an interesting benchmark to see how we went against individuals in their team, and I think we went toe-to-toe with them today.
“Of course there's that little element of disappointment that we haven’t gone through, but it will be a cracking return game when they come up to Bradford.”
Parkinson, who guided Bradford to the 2013 League Cup Final at Wembley Stadium, also said that experience meant nobody at the club would ever underestimate the importance of a potential Cup run.
“When we got to the Capital One Final the benefit the city had from that run was enormous,” he added.
“We used the run to galvanise our league form and get promotion, we used the money to clear all the debts.
“There was so many benefits from that, so every cup competition we take as seriously as any league game because the rewards are there for all to see.”
Millwall's Scott McDonald celebrates his 36th-minute goal
Meanwhile Millwall forward Scott McDonald, who got the Lions' first of the afternoon, said he welcomed the prospect of a trip to Valley Parade.
“I know a lot of people don’t want extra games at this time of year, but I think the extra game at this stage will actually do us a favour.
“Obviously performances and results haven’t been going our way, so it’s another game and another opportunity to try and make things a little bit better hopefully will help us.
“When you go 2-1 up, especially at home, you get disappointed by not being able to hold on and build on that.
"But you’ve got to keep going. You make your own luck and that's what we did. We went 3-2 down and showed a bit to get back again.
“We’re still in the draw though, and that’s the main thing."
