The winger joined from Leicester City just three weeks ago, and although he has featured in Rovers' last two matches, Marshall feels that he has yet to fully show what he is capable of.
"I've settled in really well, the lads have been great," said Marshall. "I've managed to play so it has been really good. There is still more to come, I'm still getting match fit.
"At home against Bolton was a good atmosphere, and Burnley was a good eye opener, so I'm really pleased that I was involved in both of those games.
"It is good to be playing in games like that."
Next up for Marshall is a match at his former home, the King Power Stadium, and he is anticipating a tough match.
"It is a hard ground to go," added the 22-year-old. "I remember when I was there it was very rare that we got beat at home.
"But I think with the squad we've got here and looking at their squad whichever team performs on the night is going to win I think."
Tickets will be on sale at the King Power Stadium on the day of the game, priced at £30 Adults, £27 for Seniors and Under 22s, £20 for Under 18s, £11 for Under 12s and £9 for Under 8s.
Supporters who are going to Tuesday's match should note that there are roadworks in the vicinity of the stadium at Leicester and are advised to give themselves plenty of time to get to the ground in time for the 7.45pm kick-off.
subscribers can listen to full uninterrupted commentary from 7.30pm.