Frank Lampard bemoaned the repetitive nature of Chelsea's mistakes this season after his side's defeat to West Ham at the London Stadium.
An 89th-minute strike from Andriy Yarmolenko saw the Blues throw away the chance to overtake Leicester and move up to third in the Premier League table after the Foxes' defeat to Everton earlier on Wednesday.
The 3-2 reverse saw Lampard rue his side's lack of concentration and the Blues boss challenged his players to step up mentally in similar fixtures in the future.
'It's been a good season but there have been so many of these moments,' he told Sky Sports.