All-rounder Archer, 24, hit a six to complete the Royals' chase of 176, ending unbeaten on 27 off 12 balls.

The hosts posted 175-6, with captain Dinesh Karthik hitting 97 not out.

"I'm upset about leaving but I'm going on to something that is very important to me," said Archer.

The uncapped fast bowler added his performance with the bat, hitting two fours and two sixes, was a "massive boost."

"Hopefully the England selectors will see what I can do and hopefully it can get me to where I aim to be as a contributor in the team," he said.

Barbados-born Archer, who plays for Sussex, finished his IPL stint with 11 wickets in 11 games and a economy rate of 6.76.

He was not picked in the preliminary 15-man World Cup squad earlier this month, having qualified to play for England in March after a change in residency rules.

However, he was named for the first time in one-day squads for games against Pakistan and Ireland and could still make the World Cup if he impresses in those pre-tournament matches as changes can be made up to 23 May.

Archer and fellow pace bowler Chris Jordan will gather with the rest of squad in Cardiff on Saturday, with England facing Ireland on 3 May before a five-match series against Pakistan.

Eoin Morgan's side start their World Cup campaign against South Africa on 30 May.

Archer went wicketless against Kolkata but put on a crucial 44-run stand with 17-year-old batsman Riyan Parag to get his side over the line.

England all-rounder Ben Stokes, also playing his final match in the Twenty20 tournament, made just 11 as the Royals fell to 123-6.

Parag smacked 47 off 31 balls before he was out hit wicket to Andre Russell, leaving nine to win off the finals over.

Archer edged the first ball for four through third man before hitting the next into the stands over long-off to secure victory.