The summer signing from Leicester City, was one of the standout performers as Rovers picked up an excellent point against QPR seven days ago.
Marshall has worked hard in training to earn a place in the starting eleven, with the manager challenging the wideman to get better, starting with today's match against Millwall.
"I was delighted with his performance against Queens Park Rangers," said the Rovers boss.
'He has been dying to get in the team but it has been difficult for him since he arrived because of his fitness levels and then obviously trying to get in the team.
"He's worked tremendously hard, the last couple of week especially, and I thought he gave Danny Simpson and QPR's back four a tough time.
"He put in a couple of great balls and you saw the quality that he possesses both with his left foot and his right foot.
"He's going to get better and better and get more confident as the season goes on and we need him to show that level of performance again.
"I thought his work-rate off the ball for us, and the defending side of it was very good as well.
"He's now got a chance to stake a claim to have a good run in the team."
Tickets for today's match will be on sale until the 3.00pm kick-off. Prices start from £15 Adults, £10 Seniors and £5 Juniors.