Saracens had too much for Saints while Exeter saw off Sale, Leicester beat Wasps and Quins pipped Bath.
Courtney Lawes has been ruled out for the remainder of England's Six Nations campaign with a calf injury.
Northampton denied Bath at the death to seal victory, as there were also wins for Worcester, Exeter, Sale and Harlequins.
Dylan Hartley will undergo knee surgery on Tuesday, meaning he will miss the rest of the Six Nations.
England flanker Tom Wood has agreed a contract extension with Northampton until the end of next season.
Northampton's Luther Burrell will change codes at the end of the season with a move to Warrington confirmed by the Super League club.
With Super Rugby back, individuals from both hemispheres combine to make up our latest Team of the Week.
Stuart Barnes assesses Wales' fly-half options for their Six Nations game against England, and wonders whether Chris Boyd is a Bob Dylan fan.
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