Batting great Sachin Tendulkar's son Arjun was picked "purely on the skill" and the left-arm seamer will have to prove himself at this year's Indian Premier League, the IPL franchise have said.
South African Chris Morris broke IPL auction records with his $2.24 million move to Rajasthan Royals on Thursday but all eyes were on the fate of the 21-year-old with Indian cricket's most famous surname.
In the last purchase of the players' auction in Chennai, Arjun joined Mumbai at his base price of two million Indian rupees ($27,522) having been their net bowler in the last IPL.
"We've looked at it purely on a skill basis," head coach Mahela Jayawardene said at a video conference.
"There's going to be a big tag on his head because of Sachin. But luckily he's a bowler, not a batsman. I think Sachin will be very proud if he could bowl like Arjun."
Sachin retired in 2013 as international cricket's most prolific batsman with a record 34,000-plus run and 100 centuries.
After playing under-16 and under-19 cricket for Mumbai, Arjun made his senior debut in last month's Syed Mushtaq Ali Trophy.
"We have to give him time and hopefully not put a lot of pressure on him. Just let him evolve and work his way up," former Sri Lanka captain Jayawardene said.
The franchise's director of cricket operations Zaheer Khan hoped Arjun would grow better under bowling coach Shane Bond.
"The added pressure of the name Sachin Tendulkar is always going to be there on him which he'll have to live by," former India pacer Zaheer said.
"He has to prove himself. He has to show all the coaching staff, and the team think-tank, that he belongs there.
"What he does at the highest level is something in his own hands."
Arjun has thanked the franchise for showing faith in him.
"Since childhood, I've been a die-hard fan of the Mumbai Indians ... I'm excited to join the team and can't wait to wear the blue-and-gold."