Leyton Orient coach Matt Harrold said they were not good enough in the moments that mattered after a 3-0 home defeat against Derby County.

Louie Sibley put the visitors ahead at Brisbane Road, before Brandon Cooper saw red for O's just before the break.

Nathaniel Mendez-Laing made it 2-0 at the start of the second half and, after Omar Beckles had a reply ruled out for offside, the Rams added a late third through Tom Barkhuizen. 

"The first 20-25 minutes was really good and then obviously they score a goal, probably a little bit against the run of play, and at the minute the moments are going against us and it's where we are," Harrold told the club website.

"At the time I wasn't sure [about the red card], but having watched it again I don't think we can have any complaints. It looks not great on the video, it's one of those things.

"We all accept last week probably wasn't good enough, away at Chesterfield [in the FA Cup].

"I thought we put on a good performance today but we're having a mountain to climb by conceding the first goal and then losing a man to a sending-off which has a big bearing on the game and result.

"At 2-0 we score, it's offside, I haven't seen it back and then the third goal is not good enough, bad decision-making and then the game is over.

"It's a disappointment, it's a loss, but lots of positive stuff in the first half. The moments at the minute are killing us and we need to be better."

Dan Agyei went close to a reply after coming off the bench, hitting a post, and Harrold says they need to keep working hard to end a run of eight League One games without a win. 

"The squad is getting stronger, we're getting people back from injury but we understand we're on a bad run and we need a result," he added.

"We need to keep working through it and be better in the moments and little details.

"There's a lot of good stuff but ultimately it's the moments and little details in games that are costing us and are the difference and we're on the wrong side of them too much."

Another large crowd of 8,500 looked on and Harrold had sympathy for the growing frustration among O's fans, as they prepare to visit Cheltenham Town next weekend.

"I understand the scoreline and the feeling of conceding isn't a good one so people's emotions are high," he said.

"We all want to win, we try every day to try and win the game on the weekend for these supporters who have been with us for a season and a half of pretty much pure success.

"Everyone has got to understand the journey we're on the evolution we're on, it's a process and at the minute we're in a bit of a rut.

"We're not getting the results we want but we've just got to work through it and everyone has got to stick together.

"We watched them [Cheltenham] in the lead-up to a game recently and they're competitive at home.

"He's got them fighting and scrapping on a tight pitch. We know it's going to be really hard and the lads are going to have to stand up to it and do what is needed to get a result."