SEKOU Mara scored twice as Saints sealed their progression to the fifth round of the FA Cup with a 3-0 win over Watford - to set up a tie with Premier League leaders Liverpool at Anfield.

The hosts took the lead early in the second half when Mara stroked the ball in before he struck a stunning second minutes later.

Che Adams volleyed in a third from home debutant Joe Rothwell's free-kick to seal the comfortable victory for Russell Martin's side.

The Saints boss made seven changes to the team that beat Rotherham United on Saturday - with Tyler Dibling, Jayden Meghoma, and Rothwell among the starters.

Matheus Martins, who scored Watford's goal in the initial tie, had the first effort at goal but he scuffed his shot wide of the post.

Saints had their first chance on goal midway through the first half when Dibling found Flynn Downes in an advanced position, but his shot was dealt with by Daniel Bachmann.

Watford went close to the opening goal soon after when Ismael Kone drove forward before his effort was deflected by Jan Bednarek and onto the bar.

The hosts probably should have been in front when Adams was found with plenty of space in the area but his low strike was kept out by Bachmann.

The Hornets were carrying a threat to Saints' unbeaten run and Joe Lumley had to get down well to save from Kone, following Martins' clever cross.

It had been an impressive first-half showing from Dibling and he once again nearly created a goal when he played in Smallbone - Bachmann, though, was equal to the Irishman's effort.

Saints took the lead seven minutes into the second half when Adams' touch put Mara through and he fired in at the near post.

The hosts were celebrating again soon after and they had both Dibling and Mara to thank for it.

Dibling's driving run created the space before the ball found its way to the Frenchman, who hammered a shot in from 25 yards to make it 2-0.

Sam Edozie, who had replaced Dibling minutes before, went close to adding to the advantage but he was unable to get much power on his shot.

Saints did add a third on 76 minutes when Rothwell's free-kick was volleyed home by Adams to effectively put the game to bed.

That was both Rothwell and Adams' last action of the night and they were given a rousing reception by the St Mary's crowd as they made their way off the pitch.

Mara almost completed his hat-trick late-on but his curling effort went narrowly wide of the far post.

Edozie and Sam Amo-Ameyaw both struck the post in the closing stages - with the latter missing out on a first senior goal - but it was a comfortable victory despite those misses.

Midfielder Cam Bragg was also among the academy starlets to get a late run out on another good night for Southampton's youth system.

Saints: Lumley; Charles, Stephens, Bednarek, Meghoma; Downes (S Armstrong, 78), Smallbone (Bragg, 86), Rothwell (A Armstrong, 77); Dibling (Edozie, 65), Adams (Amo-Ameyaw, 78), Mara

Unused Subs: McCarthy, Harwood-Bellis, Manning, Walker-Peters

Booked: Smallbone, Dibling

Watford: Bachmann (Hamer, 60); Dele-Bashiru, Porteous, Hoedt, Morris (Lewis, 53); Sierralta, Kone (Ince, 89), Chakvetadze (Andrews, 54); Martins, Sema (Asprilla, 54), Rajovic (Bayo, 69)

Unused Subs: Livermore, Pollock, Nabizada

Booked: Morris, Chakvetadze, Porteous

Referee: Darren Bond

Attendance: 17,844

Goals: Mara 52'

Mara 58'

Adams 76'