Morgan to captain Wales against England in Rugby World Cup warm-up
Wales head coach Warren Gatland has yet to announce his skipper for the tournament in France and says each of the preparation games could have a different player at the helm.
Centre Max Llewellyn, plus props Corey Domachowski and Keiron Assiratti, will make their Test debuts in Cardiff on Saturday.
Former England prop Henry Thomas, who qualifies for Wales through his father and has been able to switch countries under new World Rugby regulations, is among the replacements.
"We will be looking at probably having a different captain for each of the matches as we give as many as possible in the squad an opportunity to impress, but also mindful about potential combinations as we get closer to naming the World Cup squad," said Gatland.
Other players expected to be in the World Cup captaincy shake-up are hooker Dewi Lake, lock Will Rowlands and fly-half Dan Biggar.
"There is some great competition among the squad in all positions, and we've selected a team this week with a few debutants because we want to give them the opportunity to see what they can do," said Gatland.
"There is a lot to play for over the next three matches, and everyone is still in contention to make that final squad for France."
Halfpenny, 34, will reach three figures almost 15 years after he made his Wales debut as a teenager against South Africa.
"Reaching this milestone is an incredible achievement and testament to the player and person Leigh is," said Gatland. "I know it will be a very special day for him and all his family."
Wales face England in a return fixture at Twickenham on August 12, rounding off their preparations for the World Cup by hosting 2019 champions South Africa the following week.
Gatland's team launch their World Cup campaign against Fiji in Bordeaux on September 10 -- the Fijians recorded a famous victory over the Welsh in their pool match at the 2007 World Cup also in France.
Fiji progressed at Wales's expense to the knockout stages and Gatland was also a beneficiary as he was hired as Welsh coach for his first spell in charge following their exit.