The New York Knicks have been struggling on both ends of the ball lately, but coach Derek Fisher is particularly upset about his team's defense.

"We've been horrendous on the defensive end in the last six games," Fisher told reporters after practice Saturday.

New York has given up 112 points per 100 possessions over the past six games -- the second-worst defensive rating in the NBA for that stretch. They also rank 17th in opponent field goal percentage in their past six games. Not surprisingly, they've lost five of them.

Knicks coach Derek Fisher says being on the same court as Matt Barnes has "no impact" on him. Tom Szczerbowski/USA TODAY Sports

Fisher was focused on defense Saturday, but his club has struggled on offense lately as well.

New York scored a franchise-low eight points in the fourth quarter of Friday's loss to the Chicago Bulls.

Afterward, Fisher intimated that his team gave up late in the game.

"We didn't sustain the effort in the fourth quarter," he told reporters. "Everybody has to be ready each minute of the game. There just wasn't an effort in the first and fourth quarters. I don't want to be a team that gives up when there is a little rain. No matter where you are in the season, you can't allow a game to get away from you like that in the fourth quarter."

Rookie Kristaps Porzingis added: "They just kicked our ass in the end."

The Knicks are 15-19 entering Sunday's game against the Atlanta Hawks.

Information from ESPN's Ian Begley was used in this report.