Premiership: Exeter Chiefs 14-9 Bristol Bears

Pat Lam says he has taken his concerns up with RFU referees chief Tony Spreadbury

Bristol boss Pat Lam says Exeter are taking advantage of referees not properly interpreting line-out rules.

Lam claims Exeter's winning try from Sean Lonsdale in their loss at Sandy Park should not have stood as their backs joined a maul following a line-out against the rules.

Lonsdale's late try saw Exeter overcome Bristol in a scrappy affair.

Ian Madigan's three penalties had put the visitors ahead after Santiago Cordero's try right on half-time.

Exeter's victory sees them go four points clear of Saracens following their defeat at Sale on Friday night, while 10th-placed Bristol are now a point further clear of bottom side Newcastle after getting a losing bonus.

Law 18.35 and Law 18.36 b

Lam claims that Exeter regularly break two rules surrounding the line-out and says he has discussed his concerns with the RFU's referees chief Tony Spreadbury.

Law 18.35 says a player who is not in the line-out must retreat if the ball does not go 15 metres from the throw - something he claims Exeter's players do not do.

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He also says they break Law 18.36 b which says that a line-out only ends when a ruck or maul forms and the feet of all the players in that ruck or maul move beyond the mark of touch.

"As soon as the ball's thrown, their midfield backs come running forward, which they have all rights to do do in the law," Lam told BBC Radio Bristol.

"But if the ball doesn't go 15 metres and is brought down, and a maul is formed, they have to retreat 10 metres back, not hang around one, two or three metres and come in.

"It's what happened at our ground, which is why I was annoyed about it.

"They did it against Saracens, they did it against Saints. They have to go back 10 metres and they can't join until the line-out is over.

"If you have a look leading up to that second try, the ball is thrown, they're all offside, it should be a penalty, but it's not awarded, so what's the point?

"I'm not saying there's any issue with Exeter, but the referees have to know their law-book and they have to understand.

"I have no problem if you want to maul from five metres, but you have to do it by the letter of the law."

Lacklustre Exeter overcome Bears

Exeter's young flanker Sean Lonsdale proved the match-winner with the first try of his Chiefs career

Bristol took a big hit before kick-off when star full-back Charles Piutau was ruled out with a hamstring injury, forcing Pat Lam to bring Piers O'Conor into his starting line-up.

But it did not seem the phase the visitors, who started well, gaining much of the possession and territory and forcing an early penalty from Madigan.

A battle of attrition followed with two half-decent defences cancelling out two mistake-ridden offences that showed only glimpses of what they can do. Exeter knocked on a metre from Bristol's line while the visitors struggled to breach a disciplined home rearguard.

The Chiefs finally broke through in the final seconds of the half - repeated pressure under the Bristol posts allowed Exeter to send the ball out wide where Cordero dived over for his sixth try of the season.

But Exeter became more and more frustrated as they made more errors after the restart - Madigan twice striking with his boot as they went two points ahead.

It was not until the final quarter that Rob Baxter's men looked like a side top of the Premiership as young flanker Lonsdale was forced over after six minutes of pressure for the first try of his career.

But it was only a brief glimpse of a side that have struggled to live up to their early season form, and Bristol almost capitalised on another Exeter mistake five minutes from the end.

However the Chiefs held on for a key victory after Saracens' loss at Sale on Friday night.

Exeter director of rugby Rob Baxter told BBC Sport:

"You only have to look at this Premiership and see how competitive it is and how teams can beat each other and score against each other, that actually any win at the moment is a good win against anybody.

"It's probably the thing that our lads have got to settle down and get their heads.

"A few too many of them get caught up in the kind of notion that if you're one team and you've had success doing something over a couple of seasons, victories should kind of just come, because they just don't.

"Bristol came here to try and win, so you've got to play well to beat them, and for me I'm pleased we've got a win today.

"There were too many mistakes out there for me to say there aren't things for me to work on, but every team's going to have things to work on."

Exeter: Dollman; Cordero, Slade, Whitten, O'Flaherty; Steenson (capt), Maunder; Moon, Cowan-Dickie, Williams, Dennis, Hill, Skinner, Lonsdale, Kvesic.

Replacements: Yeandle, Hepburn, Francis, Lees, Van der Sluys, White, Simmonds, Devoto.

Bristol: O'Conor; Morahan, Hurrell, S Piutau (co-capt), Pincus; Madigan, Randall; Woolmore, Lindsay, Thiede, Holmes, Joyce, Vui, Lam, Crane (co-capt).

Replacements: Thacker, Thomas, Afoa, Smith, Thomas, Uren, Sheedy, Protheroe.

Referee: Craig Maxwell-Keys.

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