It’s been two years since the 25-year-old made his international breakthrough, winning his solitary cap in a laboured English success in Rome with a succession of injuries halting his progress on the big stage.
While there is one fewer rival now that Matt Stevens has retired from international rugby, younger men Alex Corbisiero and Joe Marler are still ahead of Mullan in the loosehead stakes and he admits he will have to play the waiting game to add to that lone cap.
Mullan says the opportunity to tour South Africa with England this summer, where he started both midweek matches, allowed him valuable time working with World Cup-winner Rowntree.
He said: “The tour to South Africa was a great experience for me because we got to spend four weeks with the England coaches.
“It really gave me the opportunity to work with them a lot more closely. Usually they will only be able to see you for a game here and there, so to get to chat to them for a month really helped me.
“Graham Rowntree was the go-to man for me, and he is a great coach to work with. He’s very truthful when he talks to you, there’s no messing about. That is great because if he tells you something, you take it seriously.
“Obviously the thing for me now is to get my head down. I know I’m probably waiting on an injury or a drop in form to get into the England team. Alex Corbisiero has done brilliantly since he got his chance, and then Joe Marler has stepped up as well.
“The advantage I will have is that with the new rules at international level there will be two props on the bench, so for a specialist like me there is more of a chance.
“The most important thing is to make sure I perform if the chance does come along. That’s what those guys have done.”
If Mullan’s return to the international fold has given him a confidence boost, it’s nothing compared to the impact of having a dedicated scrum coach at Sixways.
Head coach Richard Hill has already talked about the importance of having a coach entirely focused on the set-piece and in Phil Vickery he has signed up England’s second most-capped prop of all time.
And while Vickery is still cutting his teeth in coaching, Mullan revealed he was already having a big impact.
He said: “It’s brilliant to have Phil working solely on our scrum.
“As a forwards coach Nigel Redman has to look after lots of different things, so having a dedicated scrum coach is making a big difference.
“To begin with he got us on the machines looking at our techniques and then gave us some work to do on our own before coming back.
“I knew Phil a little from when I was first involved with England, he’s a really nice guy and has been there and done it all. He seems to be taking to coaching really well.
“It’s also great to work with Nigel again, having been with him when I was in the academy and with England in the age groups.”