England hooker Jamie George has recovered from a knee injury and will captain Saracens in Sunday's Premiership game at Northampton.

Northampton also make four changes, with Piers Francis and Rory Hutchinson forming a new centre partnership.

Prop Paul Hill and lock Alex Coles also come into the side.

Fifth-placed Northampton have been beaten just once at home in the Premiership this season and have won their first game in January in nine of their past 10 campaigns.

However, second-placed Saracens, whose other changes see Harvey Beaton replace Koch in the front row while Theo McFarland comes into the back row, have an excellent record at Saints and have been beaten only once in their past nine visits to Franklin's Gardens - a 23-9 defeat in the Premiership Rugby Cup final in March 2019.

George returns to action following seven weeks out after injuring his knee during England's win over Australia on 13 November.

"He was nearly ok for last week but this week he's raring to go and it's great to have him back," said Sarries director of rugby Mark McCall.

Northampton: Furbank; Sleightholme, Hutchinson, Francis, Skosan; Biggar, Mitchell; Waller, Matavesi, Hill, Coles, Ratuniyarawa, Lawes, Ludlam (capt), Augustus.

Replacements: Fish, Iyogun, Carey, Ribbans, Wood, James, Dingwall, Tuala

Saracens: Malins; Maitland, Lozowski, Tompkins, Daly; Goode, Davies; Mako Vunipola, George (capt), Beaton, Itoje, Isiekwe, McFarland, Earl, B Vunipola.

Replacements: Woolstencroft, Mawi, Milasinovich, Hunter-Hill, Wray, Van Zyl, Manu Vunipola, Segun.

Referee: Adam Leal