Ballymena United manager Glenn Ferguson has warned his players against any complacency as they begin their defence of the County Antrim Shield on Tuesday.
The Sky Blues face Championship One side Donegal Celtic at the Showgrounds.
"We are the holders so our players should be up for it and want to retain it. If we play to our potential we should win the game," said Ferguson.
"It's a distraction and takes away from the pressure of the league but we won't underestimate them in any way.
"We will be favourites and will be expected to go through but we'll have to be on our mettle and put in a performance."
United beat the Suffolk Road outfit 2-0 at the last four stage of the competition last year and went on to defeat Linfield on penalties in the decider.
DC, who lie ninth in the Championship One table. are managed by former Ballymena midfielder Paul McAreavey and also have ex-United player Conor Downey in their ranks.
Ballymena have skipper Allan Jenkins available again after suspension and are hopeful that David Cushley will be fit after hobbling off against Glentoran on Saturday, but left-back Michael Ruddy is rated very doubtful.
In the tie of the first round, Glentoran entertain Cliftonville at the Oval, with Reds manager Tommy Breslin admitting that he will make some changes to his starting line-up.
"We have a big squad so we'll give the players who were on the bench against Glenavon a run out and bring in two or three players from the reserves. We'll mix and match the team and try to progress," said Breslin.
In the evening's other quarter-finals, Lisburn Distillery, who are unbeaten after five matches in Championship One, will hope to spring a surprise against Crusaders at Seaview, while Linfield play struggling Premiership basement side Ards at Windsor Park.
Linfield will be without suspended pair Aaron Burns and Michael Gault.
Crusaders manager Stephen Baxter says he is expecting a tough assignment against the Whites, who were relegated from the Premiership last season.
"They have a top manager in Tommy Kincaid who knows Irish League football inside out," added the Crusaders boss.
"He'll come with a game plan to try and get something out of the game.
"They also have some good experienced players in their squad. Darren Nixon is a model professional who will organise them well at the back.
"We're playing well. We've not have the run of the ball this season and should have had a few more wins.
"But it's only eight games into the season and we're not concerned about it."