Ava Rowbotham has signed a new Pompey contract, subject to FA approval.
The midfielder has penned a one-year deal, with a club option of an additional 12 months.
The 23-year-old joined Pompey on loan from Lewes in March 2020, but made the move permanent in the following summer.
She has since appeared 75 times for the club and has scored seven goals.
"At 23, her best years are still ahead of her and I'm excited to see Ava continue her development with us."
Her first came against Gillingham at Westleigh Park in November 2020, with the strike securing a late 2-1 victory.
Blues boss Jay Sadler said: "It's great news that Ava has committed her future to the club.
"She is a great professional and an excellent player, who is incredibly passionate about playing for Pompey.
"Her attitude and commitment since arriving has been first class – on and off the pitch – having played a big part in us climbing the table and finishing the season as strongly as we did.
"At 23, her best years are still ahead of her and I'm excited to see Ava continue her development with us."
"It’s a huge honour and a really exciting time for the staff, players and fans."
Rowbotham added: "I’m so delighted to be signing a semi-professional contract for the club.
"It’s a huge honour and a really exciting time for the staff, players and fans. I’m really looking forward to the season ahead."