Club record signing Pedro doubled Albion’s lead following Solly March’s first-half opener by converting a 71st-minute penalty after being brought down by Hatters captain Tom Lockyer.

Carlton Morris slotted home from the spot at the other end following Lewis Dunk’s handball to set up a tense finale but Adingra capitalised on a dreadful error from Pelly Ruddock Mpanzu before fellow substitute Evan Ferguson sealed the Seagulls’ emphatic victory.

Build up to the contest was dominated by news of Albion accepting a British record transfer fee of around £111million from Liverpool for star midfielder Caicedo amid reports he would prefer to join Chelsea.

The 21-year-old Ecuador international was absent from the Amex Stadium as his current club launched their first campaign to feature European football in commanding fashion.

Luton, back in the top flight for the first time since being relegated from the old First Division in 1992, were second best on the south coast and could have lost by more as Danny Welbeck, Pascal Gross and Ferguson each struck the woodwork.

With Caicedo seemingly heading for the exit, Brighton handed debuts to Mahmoud Dahoud, James Milner and Pedro.

Brazilian forward Pedro, whose every touch was booed by the travelling fans following his £30million transfer from Luton’s bitter rivals Watford, should have opened the scoring inside five minutes but he skewed wastefully wide of the gaping goal.

The clubs were facing each other for the first time since the southern final of the Football League Trophy in 2009, with their only previous top-flight meetings coming during the 1982-83 campaign.

Luton did the double over Albion by an aggregate score of 9-2 back then but remained on the back foot, albeit the hosts appeared susceptible to counter attacks.

Albion eventually turned their dominance of the ball into a lead nine minutes before the break.

Kaoru Mitoma was afforded time and space on the left and his inviting, inswinging cross gave the unmarked March a simple headed finish from six yards out.

Albion’s advantage was almost instantly wiped out as Hatters forward Morris thumped a header too close to home goalkeeper Jason Steele from Ryan Giles’ corner before Welbeck hit the base of the right post at the other end.

Despite their limited possession, Luton, who were a non-league club as recently as 2014, were far from overawed in the first half and went into the break with reason for encouragement.

Gross fired against the outside of the left upright from a wide free-kick early in the second period as Roberto De Zerbi’s men attempted to add to their slender lead.

Brighton were in need of a cushion and it arrived 19 minutes from time when Pedro tumbled under Lockyer’s challenge before, as he had done twice in pre-season, firing into the right corner from 12 yards.

Albion looked set to ease to victory on the back of last season’s club-record sixth-placed finish which secured a Europa League place.

Yet Morris’ successful 81st-minute penalty after a cross from substitute Jacob Brown struck the elbow of Dunk briefly brought back the tension.

However, Ivory Coast winger Adingra, who was loaned to Belgian club Union Saint-Gilloise last season, thumped home just four minutes later after Mpanzu inexplicably failed to clear.

Striker Ferguson then rattled the right post with a fine curling effort.

The Republic of Ireland international would not be denied a place on the scoresheet and duly slid home Pervis Estupinan’s low cross deep into added time.