Junior Burgos: “We have to know it’s sudden death, winner go home. For this club, for the history of this club, the least we can do is keep advancing.” (Photo courtesy of the Cosmos)

UNIONDALE, N.Y. — They might be playing a team that is winless in its league, but don’t expect the Cosmos to enter their Lamar Hunt U.S. Open Cup match against Hartford Athletic overconfident Tuesday night.

The USL Championship team enters the 7:30 p.m. second-round game at Al-Marzook Field on the University of Hartford in Hartford, Conn. with a 0-9-1 mark with a last-place standing in the 18-team Eastern Conference.

Conversely, the Cosmos are undefeated in National Premier Soccer League play with 3-0-0 and have a 2-1 victory over Black Rock FC in the Open Cup under their belt.

When it comes to the Open Cup, all records get thrown out the window.

“Of course. They have a lot of quality,” Cosmos head coach Carlos Mendes said. “We’re expecting a battle. We’re expecting a good game. We’re excited. I think they have been a little bit unlucky at times in league play. They’re going to be up for the game and that will be a good challenge for us. Hopefully, we’ll play our game and play the style we want and make it difficult on them and impose our game plan. If we do that, we will have a very good opportunity. If you don’t come out ready to play a team like Hartford, you’re going to struggle early on.”

Midfielder Junior Burgos, who has participated in plenty of Open Cup games through the years, warned about any team being complacent in the competition.

“Every team can beat you in the Open Cup,” said Burgos, who connected for a pair of free-kick goals on Saturday night. “It doesn’t matter their record. They haven’t won in 10 games, so they’ll be dying to get a win and trying to put their record into the past. This is a good opportunity to do it. We’re focusing on ourselves.

“We just have to focus on what we do well. Go out there with intensity. We have to know it’s sudden death, winner go home. For this club, for the history of this club, the least we can do is keep advancing, keep the fans happy so they can keep coming and supporting us.”

The Cosmos can ill afford to repeat the slow start to their 5-0 home win over Boston City FC on Saturday night as they played to a halftime scoreless tie for the first time this season before exploding for five goals in the second half.

“We’ve got to come out better than we did [Saturday],” said David Diosa, who made his first start of the season at left back Saturday. “First half has to be key. We have to be focused and finish our chances when we have them. Our defense has been pretty good. So, we’ve got to keep that.”

The Cosmos defense — team, backline and goalkeeper — has been perfect in the league this season, not giving up a goal over 270 minutes. They capped off that shutout streak by not allowing Boston City FC to record a shot, outshooting the visitors by a 16-0 margin.

“It’s great. It feels good for the team,” Diosa said. “It makes our coaches feel safe with that. I think we’re doing pretty good in the back. It just gives the team more safety … but sometimes we do little mistakes that we shouldn’t make.”

Since the Cosmos are in the middle of playing four games in nine days, Mendes has used a rotation the past few games. For example, forward Aaron Dennis, the team’s leading goal-scorer with three in all competitions, started the game on the bench.

“It’s critical, especially this time of the season when there’s a lot of games and not a lot of time to rest guys,” Sanchez said. “It’s good for everyone because if you might not play the next guy will have your back and is going to do the job. I think everyone here in the locker room, on the roster, can fill in for the guy on the field and do the job. It’s always good to have some depth because with injuries, you never know might happen. It keeps you sharp.”

There is at least one Hartford player the Cosmos don’t need a scouting report about — forward Wojciech Wojcik, who played with the team last season. Wojcik hasn’t scored in four appearances this season.

“Great guy, great player,” Mendes said. “He’s a guy who we knew very well from last year. He’s going to work hard. Whether he’s starting or coming off the bench, he’ll give you a 100 percent. He’s a handful. He’s big striker that has good feet. So, we’ll have to be aware of him.

“They’re a hard-working team that’s organized and tactically good and we’ll have to be out our best to beat them.”