United were second best against the Blues in midweek and Jeffrey says the defeat was a wake-up call for his side who still sit third in the league standings.
“Against Linfield we worked hard enough but the quality of our play was not what it has been in recent games. Linfield did not have to work too hard for their goals - and two or three of them could have been prevented and that is disappointing for us.
“When I reflect as to where we are at - at this present time.
“This is just another lesson for us and we have to learn quickly.
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“It was a disappointing night, but it not what we do against Linfield that will define our season,” he added.
But Jeffrey knows that games against Carrick Rangers are the ones his side must target to win if they are to reach the top six this season.
“People say that the game against Linfield was a ‘big game’ and with no disrespect to Linfield it wasn’t.
“It was a game against Linfield and that takes care of itself.
“It is the teams that are in and around us - like Carrick - that are the ‘big games.’
“Aaron Callaghan has come in and done a superb job thus far and they have come off a great result against Ballinamallard United and the feed back I am getting from ther players is very positive.
“He is working them very hard and he has them well organised.
“But that is no surprise to me, because he is a student of the game.
“We have to pick ourselves up, dust ourselves down and be ready to go for a battle, like we did last weekend against Ards.
“It will be a massive battle and we have to be ready for that. Our supporters know the strides we are making and the progress we have made but we wanted to do better against Linfield.”