Southampton extended their unbeaten run against south coast rivals Brighton to eight games and moved into fifth place in the Premier League with a 2-1 victory at the Amex Stadium.
As 2,000 Seagulls fans were welcomed back for the first time following a nine-month absence, Southampton fought back after going a goal behind to secure all three points in a game which included two penalties.
Then, with 10 minutes remaining, substitute Danny Ings fired home on his return from injury after Southampton were awarded a controversial penalty, with Brighton players claiming the foul took place outside the area.
In the early exchanges the supporters looked to give their side an immediate boost, with Brighton starting on the front foot, and forcing McCarthy off his line to gather on two occasions.
Gross fired in the penalty after sending McCarthy the wrong way to put the Seagulls a goal ahead.
The home side looked to get forward at every opportunity while Southampton struggled to get going, despite their recent quick starts against Manchester United, Newcastle and Aston Villa.
Against the run of play, Saints struck the equaliser just before the break. Ward-Prowse continued his impressive record from set-pieces, crossing the ball from a corner for Vestergaard to head past Mat Ryan.
At the start of the second half, Tariq Lamptey looked to get forward down the right before playing the ball back to Gross who fired over the bar.
It was the first time the Brighton supporters will have seen Lamptey in person following his move in January from Chelsea, with his debut coming on June 23 against Leicester.
Ings struck the spot-kick into the net on his return from injury, his seventh goal of the season, and his side held on for the victory.