The 23-year old started at right-back in United's 4-2 Champions League win over Bayer Leverkusen on Tuesday night, replacing Fabio, and is now eager to cement a position in David Moyes' side after an unsatisfying 2012/13 campaign caused by injuries.
"Last season was very frustrating for me," said Smalling in the Manchester Evening News. "The first three months and the last two were horrible.
"But I have been fit since the start of the season and have just been waiting for my chance because we have a very competitive squad now.
"It is very true the manager has less room to manoeuvre because of having such a big squad. He has to go with what he feels.
"The ones like myself who have not been in the starting line-up just have to make sure in training we do as well as we can and make sure when we get our chance we let him know we are here and he doesn't forget about us.
"I was just glad to get back playing again on Tuesday night.
"Right-back is not my preferred position, but I know I can play there if needs be and after such a frustrating time you are just glad to be back and involved again."