Kieran Trippier says his recent performances have been "nowhere near" good enough after Newcastle United slumped to a sixth defeat in their last seven matches against Nottingham Forest on Boxing Day.
"My standards have dropped and my own performances have been nowhere near recently," Trippier told Amazon Prime following Tuesday's 3-1 loss, Newcastle's fourth in five Premier League outings.
"I won't shy away from it. I have had a lot of setbacks in my career and this is just another one where I need to keep going and keep believing. I have always got that belief to bounce back."
Newcastle have fallen to eight in the table, seven points away from fourth place, losing ground in the race to qualify for the UEFA Champions League, the competition they were knocked out of earlier this month.
"It is a lot of games and being in Europe has been a challenge for the club," Trippier added. "The majority of the players are not used to playing in the Champions League and it's been a challenge for the team.
"We've had a lot of injuries, the lads have given everything and worked hard for each other, but we have to start the second half of the season strong.
"Teams always go through moments and we are going through one now, but football changes quickly and for sure this team will bounce back.
"We know we can do better. The standards we have set throughout the last 18 months, we have come away from them a little bit in the last few games."
Newcastle's upcoming Premier League fixtures
Head coach Eddie Howe has bemoaned Newcastle's big injury list, which has contributed to their poor form, but insists his current crop of players are good enough to turn their form around ahead of the transfer window opening on Monday 1 January.
"My gut feeling is the answer always lies within," he said. "The players we've got here are good enough."