Roberto Martinez was at a loss to explain how Everton lost to West Brom after watching his side dominate from first whistle to last at Goodison Park.
Everton enjoyed 74 per cent possession and registered 34 shots on goal - the highest total in a Premier League game this season - on Saturday, but were unable to find a leveller after Salomon Rondon's early goal.
Ross Barkley and Tom Cleverley hit the woodwork in the first half, and Gareth Barry, James McCarthy and Arouna Kone were all wasteful from promising second-half positions.
The defeat is Everton's sixth at home this season, and leaves them six points off Manchester United in fifth.
"We didn't do anything wrong," Martinez told Sky Sports.
"Their one shot on target ends up in the back of the net. We looked bright enough to open them, we hit the post, hit the crossbar.
"The effort and the way that we play the game I couldn't fault. It is one of those moments in football sometimes that are difficult to explain."
