Referee Geoff Eltringham’s controversial penalty award helped Watford come from behind to beat Portsmouth 2-1 at Vicarage Road.

Zak Swanson fired Pompey ahead early on but Edo Kayembe cancelled that out via a second-half spot-kick Portsmouth were adamant should not have been given.

Substitute Rocco Vata then tapped home in stoppage time to complete the comeback.

Portsmouth had goalkeeper Nicolas Schmid to thank for a number of saves, including when Daniel Jebbison burst through in the fourth minute.

The on-loan Bournemouth striker was left still searching for his first Hornets goal after Schmid came out to smother his effort from 20 yards.

Centre-back Ryan Porteous did well at the other end to hook away in front of goal to foil Callum Lang, scorer of all four of Pompey’s goals in Saturday’s 4-1 win over Coventry.

Portsmouth opened the scoring in the 10th minute when James Morris only half-cleared Josh Murphy’s cross and Swanson, lurking on the right of the box, lashed the loose ball across goal and into the bottom corner.

Pompey’s tails were up, with Murphy only just off target with an acrobatic effort before Watford’s Kwadwo Baah was booked for a challenge that hurt Matt Ritchie.

The Hornets went close five minutes before the break when Porteous headed Jeremy Ngakia’s cross inches wide, but the flag was up anyway.

Watford levelled through Kayembe’s 58th-minute penalty after Portsmouth had been caught out on the counter-attack.

Freddie Potts had trouble matching Baah for speed and launched into a tackle on the edge of the box on the right.

It looked like the challenge had been made outside the area and Watford’s appeals for a penalty initially appeared to be in vain but referee Eltringham went over to consult an assistant and pointed to the spot.

Kayembe blasted high into the net after Marlon Pack was booked for dissent – and Eltringham was immediately required to quell a shoving match on the goal-line as Watford tried to retrieve the ball.

Kayembe and keeper Schmid were booked, with Pompey manager John Mousinho also shown a yellow card on the touchline.

Pompey tempers continued to boil over and Murphy and Lang were cautioned soon afterwards for fouls as Eltringham struggled to maintain control.

Baah saw a shot tipped round a post by Schmid as Watford came again. Then Jebbison somehow failed to convert at the back post after Schmid had got a touch to a shot from substitute Ryan Andrews.

Another near miss followed when Kayembe unleashed a drive that was diverted wide off team-mate Mattie Pollock with Schmid helpless.

Vata, on for Morris at the break, sealed victory deep into added time when fellow substitute Moussa Sissoko burst into the box. Schmid was able to make another save but Vata was on hand to convert the rebound.

Baah was sent off after the final whistle, receiving a second caution for running to the Portsmouth fans and taunting them with gestures.