Overall Chelsea was better in this match but they cannot score a goal against a team that is a league lower then them. This is worrying because how can you expect from them to do anything big in the premier league. I think they will even struggle in the second leg aswell, because their opponent will probobly park the bus.
Their situation is not very favorable with poor finishing in a match including in this match. Their possession of the ball was more than 70 percent and it showed that Chelsea was in full control, attempted shots were also quite a lot in this match but because of the tight defense of Middlesbrough in the match made it difficult for Chelsea players to create on target and goals.
The first leg did not go well for them but there is still hope of course with the second leg especially when it will be done at Stampord Bridge later because it is their only chance.