IF PRESSED, it's unlikely most AFLW fans would be able to name Port Adelaide's stand-in captain this year, a player who has led the Power to seven straight victories and a maiden semi-final appearance.

Janelle Cuthbertson's time as on-field Port Adelaide skipper lasted less than two games this year, rupturing her ACL in week two during the Power's win over the Western Bulldogs at the MCG.

Since then, it's been the unheralded Justine Mules-Robinson stepping into the role on game day, and her individual form has rarely been better.

Erin Phillips captured all the headlines when she crossed from Adelaide to Port Adelaide for its first AFLW season, but Mules-Robinson made the trek across town too, and also has three flags under her belt.

She's evolved from a midfielder to a hard-running and smart half-forward, proving to be the glue for tall forwards Gemma Houghton, Ash Saint and Julia Teakle and recording career-best numbers for goals and score involvements.

"When we started getting the wins, the confidence increased, and the belief in particular did as well. The girls have grown up into these amazing human beings in the past three years," Mules-Robinson told AFL.com.au.

"I've had great success and experiences at the Crows, and it's quite similar compared to the Crows in the first year, where everyone thought we wouldn't do so well. We managed to get back on top and had incredible success early in AFLW. 

"Moving over here was a bit of a challenge to try and set up a brand new side with girls who have never played at the level before. From a selfish point of view, it was good for my own development, growth and leadership.

"But I always knew once things got ticking, we'd see tremendous growth. This is the foundation now for us, stepping into next season. We've set ourselves up so well for success now." 

Close friend Phillips has seen the 29-year-old evolve from a young council concreter who'd show up to training covered in cement to a standard-setter at the Power.

"She could be laying pavers in 30-something degree heat, then would come to training with an unbelievable attitude, all this energy and love for her teammates and the game," Phillips said.

"Everyone loved just being around her because of her outlook on everything in life. 

"At Adelaide, she was a leader by example, but she didn't say a lot. Then when she came over to Port Adelaide, it was just amazing to see her evolve in that space. She was voted into the leadership group in the first year, and it was almost like she grew a little bit taller, that confidence came out even more."

Affectionately known as 'Juzzy' (with an 'ooh' sound like 'good'), the Port Adelaide media team celebrated her 75th game in part by getting her teammates to imitate her cackling laugh.

It's part-and-parcel of the infectious energy she has brought to the role.

"I love the girls, I love this club. I just tell the girls, 'We're going to have fun'. We're just kicking the footy around and being with your girls," Mules-Robinson said.

"We're in such a high-pressure environment, and I understand the stressors that come with footy. But it's like, take a seat, what are we here for? We're here to have fun, and we're here to play footy."

It hasn't all been smooth sailing, Mules-Robinson being stretched out of her comfort zone at times this year.

"It's been nerve-racking to say the least. I'm not one for public speaking or speaking in large groups, I like to have the one-on-one conversations. Definitely felt a little bit of stress and anxiety to make sure my words pre-game and at half-time are on the mark. Just making sure it's plain and simple, the girls know what they have to do," she said.

"I just take it back to what 'Loz' (Lauren Arnell, coach) has driven to us all week. Just thinking about any key messages she has, any repetition to make sure it's really embedded in our minds. Obviously catch-ups with 'JC' (Cuthbertson) too, I get her to chat at captain's run. 

"I like to mix it up, too, we had Ange (Foley) talk at half-time (against Richmond), because sometimes I'm like, 'Ayyy, what am I meant to be saying?' and Ange is such a great speaker. Even Ash (Saint) knows how to direct messages to the girls and how to talk to such a young squad."

Mules-Robinson is a dedicated soul by nature, tuning in with wife Olivia to watch English Premier League side Tottenham at whatever ungodly hour of the night the Spurs are scheduled. She's a hard worker, who never forgets to find the fun in a situation. 

"She's done an amazing job, her and the rest of the leaders. She's always really positive, but she still demands a high level, because she knows she's got the experience and premiership to back her," Phillips said.

"She knows what it takes, and I love that she's her own captain. She hasn't changed her personality in the role. She lost her father (Phil) last year, who was a big Port Adelaide supporter, and through that time, she continued to train and play.

"You know when you go to a get-together, and there's that one person who you know is coming and will make the party that much more enjoyable? She's the vibe."

Her coin toss technique might need a bit of work on Saturday, with Port Adelaide travelling to Ikon Park to face Hawthorn in a semi-final.

Mules-Robinson is well used to the surrounds of Alberton Oval, which has a reliable breeze favouring to the left of screen.

"The last couple have been at home, so I haven't had the pressure. Sometimes 'Loz' comes up to me and asks what I'm thinking. I'll suggest an idea, and she'll say, 'Nah, let's do this'. So yes, yes coach," she said with a cackle.

"But even that's a bit of fun. I never thought I'd be in this position, I'm honoured. 'JC' still does so much on-field and off-field, and she's an incredible leader and I've learned so much from her. But I'm so appreciative to be in this position."