18-year-old, Stafford-born Candlin, who is a product of Walsall's academy system, rose through the ranks at Banks's Stadium to sign professional terms in August 2017, earnling plenty of plaudits along the way.
The young forward made his Saddlers debut aged just sixteen as he took to the field during the clash with Bradford City in April 2017, and went on to make nine first-team appearances overall, along with helping John Ward's Development Squad win the 2016/17 Walsall Senior Cup.
Speaking via Blackburn's official website - Rovers.co.uk - Mitch spoke of his excitement as he begins a new chapter in his career, he said; "I can't wait to get playing and do as well as I can at a great club with a massive history. The facilities here are outstanding and they will hopefully bring out the best in me.
"I hope to gain knowledge and experience from both Damien Johnson and Tony Mowbray - I've met them both and they are really nice people. The goal is to ultimately play first team football, but I'm aware that I have to produce the goods for the Under-23s first.
"I played under two different managers at Walsall and felt I handled the physical nature of League One well and did okay when I played. Having been on the bench for Walsall in the league game against Rovers at Ewood Park last season, I saw a clinical team that played the right way and I was very impressed. I can't wait to get going with this great club."