The 30-year-old has become a fixture in the team since making his Test debut against Wales in 2012 and will now hope to inspire Scotland to a first Triple Crown in 33 years this weekend and keep the Dark Blues in the hunt for the Six Nations title.
"It's very well deserved," said Townsend after naming his team on Friday. "He (Hogg) has been one of our best players over the last 10 years but also in the history of Scottish rugby.
"Right from 19-20 years old when I first started working with him at Scotland, and then at Glasgow, it blew me away to see his passing with either hand, his kicking ability, his speed. He's been one of the best rugby players I've had the pleasure to work with.
"It's a great game to win your 100th cap, back at home, with a trophy at stake.
"He'll lead the team out and I'm sure the crowd will want to show their love for him and their appreciation of what he's done in that jersey."
'Consistent Dempsey'
Townsend, a former Scotland playmaker, has made two changes to the XV that started in a third-round defeat by France which ended his side's hopes of a Grand Slam.
Jonny Gray will replace suspended lock Grant Gilchrist to partner brother Richie in the second row, while Jack Dempsey will make his first Six Nations start at No. 8, with Hamish Watson dropping down to the bench.
Dempsey, 28, made his Scotland debut last year after a change in world rugby's eligibility rules allowed the Glasgow back-row to switch allegiance from his native Australia.
"Jack's been really consistent in training and he's taken that into the games where he's come off the bench and we feel this is the right time to see that blend," said Townsend.
Ireland, the world's top-ranked side, are the only team left in this season's Six Nations who can claim a Grand Slam.
But a Triple Crown, the reward for beating all three of the other "home" nations in any one tournament, comprising England, Scotland, Ireland and Wales, is still on offer to Townsend's men.
"It's the best Ireland team we've faced," said Townsend.
"They're on the back of a lot of big wins and they've got their strongest team they could probably put out to play us this weekend, so - while we've improved - we've got more improvement in us and we're going up against a team that's on top of their game."
