Kieran Tierney asserts he has nothing to "prove" regarding his fitness as he embarks on his second tenure at Celtic.
The 28-year-old Scottish defender has signed a five-year contract, marking his return six years after leaving for Arsenal.
During his time with the Gunners and on loan at Real Sociedad, Tierney experienced periods of inactivity, most recently due to a hamstring injury sustained at last summer's Euros, sidelining him for five months.
In response to questions about proving himself, Tierney stated, "No, nothing because I know how much I work professionally with myself, on my body, on my recovery, being as ready as I can be for games."
"So no, I'm not here to prove anything. I'm just here to do the best for Celtic and see where it goes," he added.
He continued, "I still think I have the same work rate and determination, which has always been my strong point. I try to carry them everywhere I go."
"No matter my age, what club or what position I play, I just try to give everything. That's what's got me this far."
Tierney, who emerged through the Celtic youth academy, debuted in 2015 at just 17 years old.
A successful stint followed, with the left-back securing four league titles, two Scottish Cups, and two Scottish League Cups before being drawn to London in 2019.
Thus, when the opportunity to return to Celtic arose at the start of the year, it was an easy decision.
"It's probably the easiest signing Celtic have had to make and the easiest decision I had to make," said Tierney.
"[Manager Brendan Rodgers] played a huge part, but ultimately it's Celtic. I was always happy with it."
"I've loved playing under the gaffer, played so many games under him, so successful. I'm delighted to be back with him."
"The main part of coming back here was Celtic. It wasn't to be home."
Celtic will host Newcastle United in a friendly on Saturday, and Tierney admits he will likely feel "nerves".
"It'll be amazing," he said.
"It'll be a special day, probably a bit of nerves as well because it's the first time I've done it in so long."
"I've grown up as a player, matured as a person as well, so there'll be changes."
"I'll probably take on more of an experienced player role. There are younger boys in the team that I can help along the way."