STEVE PATTERSON admits Yorkshire have little margin for error if they are to qualify for the knockout stages of the Royal London one-day Cup with four group matches remaining.

Patterson’s Vikings played out their second tie in three North Group games against Derbyshire at Emerald Headingley yesterday, a thrilling game which swung this way and that.

It means they have won only one game in four - the halfway stage of the group - and have tied two and lost one.

The top three teams advance to the knockouts.

Yorkshire are fifth in the group on four points, two points behind Durham in third and Worcestershire in second.

Leaders Nottinghamshire, Yorkshire’s next opponents at Trent Bridge tomorrow, have eight points with four wins from four.

They have posted 400-plus on two occasions, something Yorkshire would surely have done against Derbyshire but for rain ending their innings on 308-2 after 40 overs.

"It's frustrating when rain plays a part in the game,” said Patterson after seeing a revised target of 225 in 22 overs set.

“With 10 overs to go, only two wickets down, we felt we were in a really strong position.

“We were looking to get somewhere around 400, which was definitely a winning score out there.

"Then the rain came. 225 off 22 overs, it is what it is. Whether you agree with it or not, that's the target.

"Still, with the players we've got, we should have been capable of defending that score. On this occasion, we weren't good enough to do it.

"It's a point lost, absolutely.

“In the field we were poor and dropped a number of half chances. Our lack of awareness stopped us taking other chances we probably should have done.

"Had we taken some of those, we'd have killed the game very early.

"Also, with the quality of bowlers we've got, I think we can bowl better than that.

“It's very frustrating to play half the game at such a high level in terms of the batting - it's some of the best we've seen all year - and then to be so below-par in the field and with the ball.”

Billy Godleman hit a third successive century for Derbyshire and Leus du Plooy hit a superb 75 as they recovered the chase from 10-2.

David Willey was later unable to defend 17 off the last over.

“Fair play to their lads, they played well,” said Patterson. “It was swings and roundabouts, but we were still confident we’d win the game at the end.”

In their last three games, Yorkshire have tied with Warwickshire at Edgbaston and Derbyshire here. Sandwiched in between was the one-run Roses defeat on Easter Sunday.

“If you think, over the last three games, four runs have cost us four points,” said Patterson.

“And that is more than likely going to be crucial at the end of the tournament.

“With only one win from four games, I’d imagine we do need to win all, if not most, of our remaining games.

“We’ll go to Trent Bridge on Sunday, where it will be tough.

“It’s a high-scoring ground, and we’re going to have to play some really good cricket to win.

“They’re in good form. It’s going to be a big challenge, but it’s one we need to get on top of.”

Notts posted 433-7 in beating Leicestershire today at Trent Bridge. Last week they beat Lancashire at home having posted 417-7.

Willey has now linked up with England and will be unavailable for the Vikings for the remainder of this competition, as is the case with Adil Rashid.