A Saracens side led by former England captain Steve Borthwick beat the United States 20-6 in a tour match at Honourable Artillery Company grounds in central London on Tuesday.
Second-half tries from Don Barrell and James Short swung the match in the English Premiership team's favour after the sides turned round at 6-6.
Saracens outside-half Owen Farrell, the son of former England dual code international Andy, and Eagles opposite number Valenese Malifa ensured the scores remained level at the end of the first half.
But sustained Saracens pressure at the start of the second period led to a try for flanker Barrell, which Farrell converted.
Victory was sealed by wing Short's try, Farrell again adding the extras.
The United States face Portugal, Scotland A and Georgia in their remaining tour matches.