Wales could well be without George North for the remainder of their three-Test series with New Zealand after the British and Irish Lions wing picked up a hamstring injury in Saturday's 39-21 defeat in Auckland.
North was helped from the field in clear discomfort towards the end of the series opener at Eden Park.
After the match, Wales coach Warren Gatland said: "George has a hamstring injury and we'll assess him tomorrow [Sunday] to see if he'll be able to play a further part in the tour.
"It's very disappointing because I thought George was outstanding and his battle with Waisake Naholo was a great part of the game."
Prior to Saturday's game, the Welsh Rugby Union confirmed Aled Davies had arrived in New Zealand to take the place of fellow scrum-half Lloyd Williams, who will return home on Sunday with fellow injury victim Paul James.
Wales subsequently announced the additions of versatile back Rhys Patchell and teenage winger Keelan Giles to their touring party, amid concerns over the fitness of North and Gareth Anscombe, who took a knock to the hip.
Despite their injury woes, Gatland believes his side will improve after they threatened to earn a shock series lead against the All Blacks, before falling away in the final quarter.
"If you look back at us in competitions and tours, sometimes we've been caught short in the first Test and we've always improved in the second and third Tests, so we're confident we'll get better next week and get better for the third Test as well," said Gatland.
"Sometimes the learning takes place out in the middle and it doesn't matter what we do on the training field and as coaches, you've got to be out there in the middle to experience that relentlessness the All Blacks bring.
"We feel like we get better the longer we are together. I think we will have learned a heck of a lot from that."