Despite turning in a string of impressive performances in recent weeks, the Jags have been left with little to show for their efforts.
A poor defensive display saw them ship three goals to Aberdeen at Firhill a fortnight ago and they conceded another four to Dundee United as they crashed out of the League Cup on Wednesday night.
Boss Archibald takes his side to McDiarmid Park tomorrow afternoon and the former Jags defender has no doubt about where the SPFL Premiership newcomers must improve if they are to end their three-game winless run.
He said: "The boys had five or six clean sheets in-a-row at the back end of last year. It is about getting confidence.
"They didn't play too badly on Wednesday. I hate when you pick up the paper and someone else has said that and you think, 'what are you talking about?' It is hard for me to sit and say that.
"The plus point was that Gabby (Gabriel Piccolo) came back and did really well.
"He had a horrible debut against Aberdeen but I thought he handled David Goodwillie and the other strikers fine.
"We work them all the time. There is not a day goes by that we don't work the back four. It is vital that we do that whether we win or lose.
"It is all about communication, especially when you have got young lads in the team.
"They don't seem to talk a lot. They talk a lot in the dressing room and when they are on nights out but they don't speak with each other on the pitch and communicate with each other. It is something we work on all the time."
While Thistle saw their League Cup dreams come to a premature end on Tayside, St Johnstone emerged comfortable winners against Championship leaders Hamilton Accies.
Two goals from Stevie May inspired Tommy Wright's side to success at New Douglas Park on Tuesday evening. And Archibald admits the dangerous Perth attacking line will provide a stern test.
He said: "I have been very impressed with them. They are hard to break down and they have got experience right across their back line.
"They have also got a threat up front with Stevie May, Nigel Hasselbaink and Steven MacLean, three players that I really like.
"I don't think May scored against us last year. Stevie kicked on in the second half of the season. Earlier in the season he was playing as a lone striker and he is better with two up top.
"He is a very good player and obviously a threat. The boys know a lot about him. We will touch more on the ones they don't know and the guys they haven't played against."
Archibald made several changes to his starting line-up for the United cup clash from the side that drew 1-1 with Kilmarnock on Premiership duty last weekend.
Defender Piccolo, midfield pair Ross Forbes and Mark Kerr and forward Christie Elliott all impressed against Jackie McNamara's side, with Elliott briefly reducing the Jags' arrears before Goodwillie completed his hat-trick in the final minute.
And Archibald was delighted to see his fringe stars shine.
He said: "I thought all the boys that came in did really well. Gabby, Christie, Kerzo and Forbesy all staked a claim to get a starting berth this weekend.
"I am delighted for Gabby and Christie. I said to Christie before the game he has got this supersub tag and he showed on Wednesday night that he is not that, he was very good.
"They have definitely done themselves no harm."