The Jags captain has been placed in interim charge of first-team matters following the departure of McNamara.
The Firhill hierarchy met last Friday to discuss who would lead the side for the remainder of the Irn-Bru First Division campaign, and have placed their faith in Archibald for the time being as they sift through a range of applications.
It has proven to be a frustrating start to life in the dugout for Archibald as he has seen fixtures at Cowdenbeath and Raith Rovers postponed, and title rivals Morton open up an eight-point lead at the top of the table having played three games more.
Thistle are prepared to take their time to make sure they appoint the right man for the job, and Archibald is determined to keep the focus on football while he is in the hotseat as he prepares for a crunch clash at Cappielow this weekend.
He said: "The board put a statement out on the website on Saturday and what they told me was very similar to that. Not a lot has changed in my position, there have been no games for them to judge me as a manager or how the team is doing. Nothing has changed, to be honest.
"Personally, I am happy to continue doing the job I have been asked to do. My main concerns are for the players. There has been a lot of speculation going around.
"On Friday there were people coming out and you don't want anything to unsettle the dressing room. My focus is on winning games. The boys can't take their minds off that and they shouldn't because they are professionals.
"They have been quite relaxed. It gives them something to talk about when they see things in the paper. You can't hide away from it, it is just one of these things. People buy newspapers and you can't get away from it, even if it is speculation.
"It doesn't affect me and it won't affect us on a Saturday. Come the game time, your head has to be on the match and that is all that matters."
Thistle have yet to take to the field since McNamara and assistant Simon Donnelly left the club almost a fortnight ago, with their back-to-back postponements leaving them with a hectic fixture schedule over the next four weeks.
Archibald is set to finally take charge for the first time on Saturday and the interim boss cannot wait to get down to business.
He said: "We gave the boys the weekend off and were back in yesterday. It was disappointing to see the game called off. We had trained and prepared well, but it wasn't to be. It is frustrating because we all want to play and the boys were up for it.
"The boys are frustrated and so am I. We want to get back on the pitch. We worked on a couple of things on Thurday and Friday and that was the most disappointing thing, that we weren't able to test it in a game because we had prepared well.
"It happens in football though. It just makes it an even bigger first game this weekend against Morton."