Mthiyane initially joined Pirates at the beginning of the season after helping Chippa United finish in the top eight in 2015/16 for the first time.
However, he suffered a knock and failed to play a single match for Bucs amid competition at left-back from vice-captain Thabo Matlaba, Patrick Phungwayo and teenager Tercious Malepe.
The 28-year-old this week joined Arrows on loan for the second half of the campaign, having snubbed a prospective return to the Chilli Boys.
"Obviously when you arrive there [at Pirates] you need to hit the ground running and in your position you've got to compete," Mthiyane tells KickOff.com.
"My situation was I suffered an injury and when you suffer an injury and the season starts and the person you are competing with is not getting an injury, then obviously he's fit enough. It's not easy to come back after that, so you can't compete much.
"But when you arrive at a club like that you've got to compete and be lucky that you don't have recurring injuries. But it was unfortunate that I didn't play."
Meanwhile, the versatile Mthiyane says he is comfortable playing at fullback or at left wing, having notched four goals in 26 league outings as a wingback last term. The former AmaZulu and Thanda Royal Zulu attacker also operated as a second striker for Amabhubesi where he netted 14 goals in the NFD in 2012/13.
"The position obviously I grew up playing was left wing until Roger Sikhakhane switched me to be a left-back," he explains.
"Even there at left-back I'm good too, so both positions I'm comfortable. But I'm not coming here to relax since I'm close to home and people who know me, I don't think it'll make me change focus. You are focused everywhere you go and I'm just here to work.
"Having said that, Arrows is a team that is stable and their style of play I feel I can fit in. Actually all the people at the club said good things about the club, that's why I came here."
Mthiyane's first game with Arrows will be on Wednesday against log leaders SuperSport United at Lucas Moripe Stadium.