The double Grand Slammer will climb to the top of a pile that also contains Wales and Lions greats Gareth Edwards, Terry Holmes, Robert Jones and Rob Howley.
Phillips is currently tied with Dwayne Peel on 76 but is set to surpass his former teammate in the RBS 6 Nations clash.
And Peel, a Lions Test starter on the 2005 tour to New Zealand, expects his successor to become a rugby centurion.
"You never know what's around the corner, but I think it's probable Mike will go on to hit 100 caps," Peel told the South Wales Evening Post.
"As long as he stays fit, he should get there.
"He's obviously a good player. His biggest strength is his competitiveness.
"That goes a long way to making him the player he is."
Peel, who is currently out of action with a fractured jaw, was in the stands at Murrayfield and reckons Wales can defend their Championship crown against England.
Wales must win by seven points or more to stop the old enemy winning the title.
"It would be great for the boys to win the title," said Peel.
"I thought they did really well to get a result up in Scotland.
"It wasn't the prettiest game, but they fronted up and played to the conditions."
The former Scarlets, now at Sale, has seen little international action in recent years but is still desperate to pull on the Three Feathers.
"Being at the Scotland game does make you realise how much you miss international rugby - the atmosphere and everything.
"Do I still want to play for my country? Of course. You have to have those ambitions. It means a huge amount."