The Exiles opened up with an impressive 43-16 victory at Bordeaux-Begles last week and Smith has named another strong team for the visit of Mont-de-Marsan in Pool One.
The visitors prop up the Top 14 but they gave Gloucester an uncomfortable evening in France last week, and Smith has resisted the temptation to give some of his star men the weekend off.
Captain Declan Danaher returns to the back row in place of Ofisa Treviranus and England Under 20-star Anthony Watson will start at full-back in place of Steven Shingler, who drops to the bench.
London Irish: 15 Anthony Watson, 14 Topsy Ojo, 13 Jonathan Joseph, 12 Guy Armitage, 11 Sailosi Tagicakibau, 10 Ian Humphreys, 9 Tomas O'Leary, 1 Max Lahiff, 2 David Paice, 3 Halani Aulika, 4 Bryn Evans, 5 Matt Garvey, 6 Declan Danaher, 7 Jamie Gibson, 8 Chris Hala'ufia.
Replacements: 16 Scott Lawson, 17 Jerry Yanuyanutawa, 18 Leo Halavatau, 19 Kieran Low, 20 Ofisa Treviranus, 21 Conor Gaston, 22 Steven Shingle, 23 Jack Moates.
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The Barbarians are one of the top invitational rugby sides with a long history and classic rugby jersey.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Lions get ready for their matches with this green training jersey. It's what the players wear. Get in the Gear!
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
The Lions are ready to get their Australia tour underway. They arrive in Perth on Monday.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.