Lewington's early score put them ahead, but two Tom Hardwick penalties made it a one-point game at half-time.

Ben White's try put Leicester ahead, but Sarries took advantage after Telusa Veainu was sin-binned as Dom Morris crashed over to restore their lead.

Lewington's second try with 10 minutes left sealed the win which meant Leicester stay second-from bottom.

Saracens, who are already relegated following salary-cap breaches, move on to -63 points.

England did not want to risk Mako Vunipola being in their camp ahead of the Six Nations clash with Wales

They started the game with England prop Mako Vunipola in the side after he was stood down by the national team earlier in the week in the wake of the coronavirus outbreak.

The prop had flown back from Tonga via Hong Kong, which has been affected by the virus since January, but has not displayed any symptoms.

It was his cousin Manu, though, who set up the first try as his nicely-timed pass allowed Lewington to scythe through the defence after 17 minutes to end a lovely passing move from a lineout 22 metres out.

Leicester lost fly-half Johnny McPhillips to a knee injury just seven minutes into his first Premiership start, and it was his replacement, 20-year-old Hardwick, who got them on the scoreboard with two successful kicks.

The Tigers defence did well early in the second half as Saracens started to probe, and they were rewarded when Joe Batley broke from the halfway line and popped the ball to White who raced in from 30 metres to give them a six-point lead.

After Manu Vunipola's penalty had reduced the deficit, Leicester full-back Veainu was yellow-carded for a deliberate knock on and Sarries pounced as Dom Morris blasted through the short-handed defence.

With an extra man on the field, Sarries came alive and Lewington was on the end of another Manu Vunipola-inspired passing move to cross for his second, while youngster Ali Crossdale had a late try chalked off after teammate Ben Spencer knocked on in the build-up.

Saracens director of rugby Mark McCall:

"We've won nine out of our 13 games this season, we'd be second in the table.

"Given that we haven't picked many of our international players for many of our league games and everything that's going on behind the scenes, I can't speak more highly of our playing group, the positives for us this year is just how many younger players have got exposure and have relished their chances and opportunities.

"Sean Reffell had an outstanding game at seven, he's a very young man and to play against a pack the size of Leicester's pack and make the contribution he did was great, Dom Morris had a great game at 13.

"We had a nice balance in the team between some experienced players who fronted up and some younger players who are on the start of their journeys and overall it was a good game for us."

Leicester head coach Geordan Murphy:

"At 7-6 at half time I thought we were still in the game, I thought the endeavour was there and the guys were working very hard for each other.

"I thought we could have had another couple of penalties to keep that scoreboard ticking. At 60 minutes when we scored a great try I thought, six points up 20 minutes to go, I thought we were really in control.

"A couple of big moments go against you, the Veainu yellow card really hurt. Did he mean to knock it on, or was he trying to intercept?

"It's a really tough one and I'll need to look at it more closely but it is what it is, you get a yellow card and Saracens just stretched us in that period and tested our fitness.

"Certainly there were things we got wrong in the game, but ultimately it was not good enough."

Saracens: Gallagher; Segun, Morris, Barritt (capt), Lewington; Manu Vunipola, Wigglesworth; Mako Vunipola, Woolstencroft, Koch; Skelton, Kpoku, Isiekwe, Reffell, Clark.

Replacements: Singleton, Barrington, Lamositele, Hunter-Hill, Rhodes, Spencer, Whiteley, Crossdale

Leicester Tigers: Veainu; Holmes, Thomas, Eastmond, Hughes; McPhillips, White; Leatigaga, Polota-Nau, Heyes; Spencer, Batley, Wells, Reffell, Kalamafoni (capt).

Replacement: Kerr, Bateman, Cole, Green, Boladau, Simmons, Hardwick, Worth.

Referee: JP Doyle (RFU)