Arsenal manager Arsene Wenger felt his players lacked commitment in tackles during the 4-0 defeat to Southampton and conceded the hosts were much sharper at St Mary's Stadium.
Wenger's men missed the chance to go top of the Premier League on Saturday as they were undone by a Shane Long brace and further goals from Cuco Martina and Jose Fonte.
Following Monday's victory over Manchester City, hopes were high for a sustained title challenge from Arsenal, but Wenger was left unhappy with his side's lethargic display at Southampton.
"I don't much take too much notice of the scoreline in my consideration but we lost too many challenges, they were sharper than us," he told BT Sport.
"We were unlucky on the first one [goal]. The first shot on goal from the right-back [Martina] goes in the top corner.
"The second one was a foul on [Laurent] Koscielny and that was the turning point but the referee didn't see it, then we were exposed on counter-attacks.
"It's a disappointing result but I have to say well done to Southampton.
"In many challenges we were second best. The referee let a lot go as well but when you're not dominant that's the price you pay."
Surprise leaders Leicester City remain two points clear despite their defeat to Liverpool earlier on Saturday, with City's 4-1 win over Sunderland moving them just a point behind Arsenal.
Asked about the unpredictable nature of this season's Premier League, Wenger added: "I said many times it's down to consistency to fight in every game and find the resources to produce top-level performances.
"[It] was a very, very physical game and this team [Southampton] fights for their life - as long as we couldn't score the first goal you could see it would be a difficult game."