Ojo replaces Anthony Watson and the rest of the back-line remains unchanged from last week's win over Mont-de-Marsan.
Shane Geraghty again captains the Exiles in their unlikely bid for qualification to the knockout stages.
In the pack George Skivington returns to the second-row to partner Matt Garvey who moves from flanker.
Bordeaux Begles have altererd their half-backs and full-back following the defeat to Gloucester last time out.
Nicolas Sanchez and Baptiste Serin replace Camille Lopez and Julien Seron at fly-half and scrum-half, while Lachie Munro is replaced by Felix Le Bourhis in the No.15 jersey.
Hugh Chalmers takes the number seven shirt from Rohan Kitshoff for Bordeaux, who travel to the Madjeski Stadium trying to get their first win of the tournament.
London Irish: 15 Jonathan Joseph, 14 Topsy Ojo, 13 Guy Armitage, 12 Steven Shingler, 11 Marland Yarde, 10 Shane Geraghty (capt), 9 Jack Moates, 8 Alex Gray, 7 Jamie Gibson, 6 Kieran Low, 5 Matt Garvey, 4 George Skivington, 3 Leo Halavatau, 2 Brian Blaney, 1 Jerry Yanuyanutawa.
Replacements: 16 Gerard Ellis, 17 Max Lahiff, 18 Richard Palframan, 19 James Sandford, 20 Declan Danaher, 21 Alex Gray, 22 Anthony Watson, 23 Darren Allinson.
Bordeaux-Begles: 15 Félix Le Bourhis, 14 Rafael Carballo, 13 Charles Brousse, 12 Michel Denetre, 11 Thierry Brana, 10 Nicolas Sanchez, 9 Baptiste Serin, 8 Damien Larrieu, 7 Hugh Chalmers, 6 Gauthier Gibouin, 5 François Tisseau, 4 Andrew Chauveau, 3 Nicolas Descamps, 2 Hikairo Forbes, 1 Jefferson Poirot.
Replacements: 16 Fabien Rofes, 17 Franck Labbe, 18 Tamato Leupolu, 19 Yassin Boutemane, 20 Louis Madaule, 21 Camille Lopez, 22 Julien Seron, 23 Carolis Navickas.
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
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 All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
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.