Stalwart centre O'Driscoll will match former Wallabies scrum-half Gregan's mammoth total this weekend as Ireland field an unchanged line-up from their impressive 26-3 Wales thumping two weeks ago.
O'Driscoll is now in line to surpass Gregan's record before retiring at the end of this Six Nations championship.
The 35-year-old will notch 131 Ireland caps in west London on Saturday, with his eight Lions honours bumping him up to equal status with Gregan.
Head coach Joe Schmidt has made two changes to the replacements bench, one enforced with lock Iain Henderson replacing Dan Tuohy who broke his arm against Wales.
The other change sees Jordi Murphy replace Munster's Tommy O'Donnell, with the Leinster flanker primed for his international debut if he joins the fray.
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