Dennis has three goals in nine league appearances for his Belgian club this season, and also notched twice against Real Madrid in the Champions League earlier in the campaign.
McGoldrick thought he had equalised just two minutes after Son's opener, but VAR replays showed that Lundstram's toe had been marginally offside in the build-up - a decision that was so close it took nearly four minutes to make.
West Ham's woes continued as Manuel Pellegrini's men were beaten 3-0 at Burnley to stretch their winless streak to seven games.More news: Arsene Wenger Predicts Winner Of Liverpool vs Man City
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"We have got so much improvement to do because the gap was too big a year ago between us and the top two, and we want to try and close that".
Goals from Tammy Abraham and Christian Pulisic were enough to lift the Blues up to second place in the Premier League with 26 points from 12 games, before Manchester City clash with leaders Liverpool at Anfield on Sunday.
United haven't fared much better than the North London club having conceded 11 goals in the same number of matches despite spending huge £80m on former Leicester City defender Harry Maguire.
David McGoldrick thought he had levelled nearly immediately, but after a three-minute delay the goal was ruled out for Lundstram being millimetres offside in the build-up.
Spurs were given a fortuitous lead after halftime by Son Heung-min, but George Baldock's equaliser earned Sheffield United a 1-1 and extended their unbeaten run to five league games.
He told reporters, via Metro: "I think if you look when I was in Scotland [with Celtic] we had defensive records as well". Newcastle trailed at home to Bournemouth but goals by DeAndre Yedlin and Ciaran Clarke sealed a 2-1 win.