England and Arsenal goalkeeper Siobhan Chamberlain says there will be "no complacency" from the FA Women's Cup holders against Millwall Lionesses.
The record 13-times winners travel to the Den for Sunday's fifth round tie.
"Millwall will definitely be a test for us," Chamberlain, 31, told BBC Sport. "We know we've got to be at our best to beat them. We will not be complacent."
"Arsenal have done exceptionally well in the cup and, this season, we will be looking to do exactly the same."
Millwall drew 0-0 at home to London Bees on Wednesday in their first Women's Super League Two game of the season.
Speaking to BBC Sport about Sunday's cup tie, first-team manager Dan Mlinar said: "We are massively looking forward to it.
"If we can't get ourselves up for a game against Arsenal, at the Den, then we're in the wrong game.
"You either look for a little team away from home, or a big draw at home. It cannot get bigger than the holders."
Arsenal lifted last season's FA Women's Cup at Stadium:MK, but this year's final will be held at Wembley for the very first time.
|Arsenal and Milwall in the FA Cup|
|Arsenal Ladies||Millwall Lionesses|
|Winners: 13 times||Winners: Twice|
|Runners-up: Once||Runners-up: None|
"With the final being at Wembley, it is a dream for every single player from every club to get to that final," Chamberlain added.
"Obviously the league is the bread and butter, week in week out, but the FA Cup is something special, that everyone wants to win."
Millwall beat Lowestoft Town LFC and Portsmouth FC Ladies to reach this stage of the competition.
"We will make one or two changes, just to keep it fresh," Mlinar said.
"If you are going in with heavy legs against Arsenal, you are going to be in trouble from the start. We need to recover right and train right before Sunday, because Arsenal did not play in mid-week."