OXFORD United have been here before.

Three defeats in their first four Sky Bet League One games is not yet as bad as the starts of 2018/19 and 2020/21, when it took the U’s a good couple of months to get going.

Injuries were a factor then, too, and if Marcus Browne turns out to be sidelined for a long time then even the harshest critic would admit United have been unlucky.

Right now, the pattern of results is very similar to 2019/20. That year, the U's took four points from their first five games and picked up in mid-September.

RATINGS: Every Oxford United player marked out of 10 for Lincoln performance

In all three of the years mentioned above, the U’s finished much stronger than they started and twice reached the play-offs.

The difference this time is that League One is much more competitive and last season showed the margin for error is smaller.

It makes it so frustrating that United have not taken advantage of a relatively kind start to the campaign.

Derby County away on the opening day was always going to be tough, but the U’s would certainly have targeted more than three points from the games against Cambridge United, Bristol Rovers and Lincoln City.

READ MORE: Karl Robinson 'understands there will be criticism' after Lincoln defeat

Maybe I am being unfair on the Imps, who are unbeaten under new manager Mark Kennedy and looked well-organised. They could surprise a few teams this season.

It was almost the perfect away performance from the visitors, who came away with a 2-1 win despite having just three shots on target and 35 per cent possession.

Like Bristol Rovers on Saturday, Lincoln took their chances and United did not.

The U’s have been more secure so far this season and one game does not change that, but they made errors in the build-up to both goals.

Neither Elliott Moore nor Stuart Findlay tracked Tom Hopper for the opener, while Sam Long tackled thin air for Anthony Scully’s customary strike against United.

WATCH: Highlights of last night's game

The U’s showed more urgency going forward, but Hopper’s goal briefly knocked the stuffing out of them after a positive first 20 minutes.

They needed to be better after the break and if Cameron Brannagan had scored four minutes into the second half you would have backed them to take something from the game.

United still had plenty of chances with Billy Bodin taking his eye off the ball at the back post, as well as Moore and Findlay heading off target. Kyle Joseph and Browne also went close with efforts from range.

After seeing the U’s create so little on Saturday, that is an improvement.

But United are still struggling to get Matty Taylor into the game and have lost the ability to drive out from the back since Luke McNally left for Burnley.

The substitutes made a difference and I would like to see Joseph start alongside Taylor against Morecambe this Saturday, even if it leaves the U’s with fewer options on the bench.

It feels crazy to call a match in August a ‘must-win’, but it is starting to feel that way.

This weekend kicks-off a run of fixtures against the division’s current bottom three, with a trip to Cheltenham Town and home game against Burton Albion falling on the next two weekends.

Seven points would get the U's back on track and that should be the minimum expectation. The margin for error is as small as ever.