Taulupe Faletau could make his return to Test match rugby on Saturday, handing Wales a boost ahead of the key game against South Africa.
The No 8 played 55 minutes of Bath's 16-9 Aviva Premiership victory over Bristol last Friday, and appears to be in line to feature in Wales' final game of the autumn series in Cardiff.
It was Faletau's first appearance in competitive rugby since suffering a knee ligament injury on his Bath debut against Northampton in early September.
As a result, the 26-year-old missed Wales' November fixtures against Australia, Argentina and Japan.
Wales' interim head coach Rob Howley will name his line-up on Thursday, and might decide to include Faletau as a substitute, using Warburton at blindside and Justin Tipuric reclaiming the number seven shirt after missing last Saturday's 33-30 victory over Japan.
Wales assistant coach Neil Jenkins said: "I think Toby [Faletau] is just a ridiculously good rugby player.
"Watching him in training, he looks like he hasn't been out [injured]. He is a class act, a world-class number eight, one of the best on the planet.
"For us to have him fit and back in the mix and back training is a fantastic addition to our squad."
Faletau's return for Bath means that he could start against South Africa, switching Gloucester's in-form Ross Moriarty to blindside flanker alongside Faletau and skipper Sam Warburton in the back row.
South Africa head into Saturday's game on the back of a 20-18 defeat to Italy, and a total of seven losses this year. Wales have only beaten South Africa twice in 31 attempts - in 1999 and 2014.
"South Africa do play a certain brand of rugby - an intimidating and physical brand of rugby - and I have no doubt they will come with that on Saturday," Jenkins added.
"Physically, they will try to out-muscle us on Saturday, there is no doubting that, and I think they will come route one.
"We've got to be ready - physically and mentally - for that and make sure we impose our game on them."
A win against South Africa would give Wales their third autumn victory, a feat previously achieved in 2002, with wins over Romania, Fiji and Canada.
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