Tottenham boss Mauricio Pochettino was left wondering why his side were unable to hold onto a one-goal lead against Newcastle United on Sunday.
Spurs led at White Hart Lane when Emmanuel Adebayor scored in the 18th minute but eventually went down 2-1 to the Magpies following second-half goals from half-time substitute Sammy Ameobi and full debutant Ayoze Perez.
Pochettino felt his Spurs side were in a good position at the break but could not explain why they conceded twice in the second half which forced them down to 11th place on the Premier League table.
"It is not something where you can analyse the action, sort the tactical situation and move the players," Pochettino said.
"With mentality, we need to work hard. It is not easy. We need to be more strong, like a team. This is our challenge.
"We need to speak, we need to create a different situation on the training ground and work.
"We know how but always you need to spend time to work in this area. It is not the same as in physical or tactical situations. It is a different area."
