There's been an update on Halfpenny as he battles concussion symptoms

Leigh Halfpenny's return to rugby is not going to happen this weekend as he's failed to recover from the effects of concussion.

The full-back sustained the issue in a tackle by Samu Kerevi during a 9-6 victory over Australia on November 10, a challenge which Warren Gatland criticised in the aftermath.

He missed the 74-24 victory over Tonga, a match he was always likely to be rested for anyway, but didn't recover in time for Wales' final November international against South Africa, a game which Gatland's side won 20-11, with Liam Williams slotting in the 15 jersey.

Speaking two weeks ago Rob Howley gave his reasons for Halfpenny's absence against the Springboks saying "He did some training on Saturday morning and was feeling a little bit light-headed".

According to the BBC Halfpenny won't be considered for this Friday's European Champions Cup game with Ulster at Parc Y Scarlets.

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There is better news for second row Jake Ball, he has passed his initial HIA return-to-play protocols after picking up a knock in the 29-20 defeat at Glasgow Warriors on Saturday.

But another of their squad, Blade Thomson, remains out of contention too because of a head injury.

Thomson suffered concussion in the Scarlets’ defeat to Edinburgh on November 2. It meant that the former Hurricanes backrow wasn't able to make his debut for Scotland in the Autumn after receiving his first call-up. Gary Graham would eventually be drafted into Gregor Townsend's squad instead.

The Scarlets are currently bottom of Pool 4, without a win in their opening two matches, having lost 14-13 at home to Racing 92 in round 1, followed by a 45-27 defeat against Leicester Tigers at Welford Road in round 2. Wayne Pivac's side are likely to need maximum points from their double-header with Ulster if they're to achieve an escape act from the pool stage like they did last season following two opening defeats.

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