(CNN) -- Newcastle United clinched an immediate return to the English Premier League with six matches left in the season after promotion rivals Nottingham Forest were held to a 0-0 draw by Cardiff on Monday.
The result left Chris Hughton's team 15 points clear of third-placed Forest ahead of their 41st of 46 matches later in the evening against Sheffield United, which they won 2-1.
That victory put Newcastle six points clear of second-placed West Bromwich Albion, who had to come from behind to draw 1-1 with relegation-threatened Watford and have played one more match.
Newcastle were relegated on the final day of last season, ending 16 seasons in the top flight after a disappointing campaign which saw owner Mike Ashley unsuccessfully try to sell the club following criticism by angry fans.
Forest can still win automatic promotion, but trail West Brom by 11 points with four matches to play.
Otherwise the former European champions will have to compete for the final Premier League place in the end-of-season playoffs, which feature the teams placed third to sixth in the table.
Cardiff consolidated fourth place, three points behind Forest, with Swansea a further four points back after Monday's 3-0 victory over Scunthorpe.
Former Premier League team Leicester, seeking a second successive promotion, retained sixth place after ending a run of four defeats with a 4-0 hammering of Queen's Park Rangers.
Bottom club Peterborough were relegated to the third division following a 2-2 draw at Barnsley only one season after winning promotion.