Southampton and West Ham suffered shock defeats on Saturday as the Championship title race took an unexpected twist.
Nigel Adkins' Saints and Sam Allardyce's Hammers may remain odds-on to finish in the top two of the second tier this term, but their respective setbacks at the hands of Doncaster and Burnley, respectively, have handed the chasing pack fresh incentive.
Cardiff, Middlesbrough, Leeds and Brighton, the four teams who currently occupy the play-off places, all took full advantage by securing three-point hauls to cut the gap and increase the pressure heading into the hectic festive period.
Such is the congested and competitive nature of the Championship that there are a host of clubs who will still retain realistic play-off ambitions, with Birmingham down in 14th spot just six adrift of the sixth-placed Seagulls, and with the benefit of three games in hand due to their Europa League exertions.
Here, skysports.com assesses the recent form of the current top six as they approach the halfway point in their battle to secure a place in the promised land of the Premier League.
Southampton remain in pole position to secure back-to-back promotions with Adkins' side having enjoyed an astonishing perfect 10 from their fixtures at fortress St Mary's this term, with their attacking verve and defensive resilience proving too much for their opponents. But on their travels they have struggled somewhat of late, with their defeats by Bristol City and Doncaster extending a run which has seen them win just one of their last seven away from the South Coast. Leading scorer Rickie Lambert, who missed the weekend defeat by Rovers through injury, is clearly key to their ambitions.
Sky Bet promotion odds: 4/9
West Ham have recovered well from the trauma of relegation from the Premier League and can secure an immediate return under the stewardship of summer appointment Sam Allardyce. The former Bolton and Newcastle boss steadied the ship after Avram Grant's time at the helm, retaining Rob Green and Carlton Cole over the summer, while also recruiting Kevin Nolan. Allardyce's approach may not suit all, but it is difficult to argue with the results they are achieving, with their recent away win at Middlesbrough an example of how to overpower a promotion rival.
Sky Bet odds: 4/11
Given their play-off misery of the past two seasons, Cardiff have an added incentive to secure a berth in the top two come the end of the current campaign. A second successive setback in the end-of-season shake-up brought the curtain down on Dave Jones' tenure and saw Malky Mackay installed at the helm. The Scot has settled well into life in Wales and has benefited from the goals of compatriot Kenny Miller, while Peter Whittingham remains a key figure in midfield. Progressing to the Carling Cup semi-finals has proved to be no distraction, and the real possibility of a Wembley final awaits as they tackle Crystal Palace over two legs in their semi-final.
Sky Bet odds: 5/2
Boasting the best defensive record in the Championship alongside West Ham, Middlesbrough are firmly in the frame to challenge for elevation this season. Popular manager Tony Mowbray has ensured that the dark days of Gordon Strachan's reign have been forgotten and has moulded the side he once played for into a tough to beat unit who have suffered fewer defeats than the current top two. The concern for Mowbray and the Riverside faithful will be their current ability to find the net, with Boro averaging just over a goal every game, which has contributed to just three wins from their 10 fixtures on home soil this season.
Sky Bet odds: 11/4
Simon Grayson has seen his side produce an excellent response to their 5-0 home humbling by Blackpool at the start of November with four victories from their following five fixtures, with their only setback in that run coming against Barnsley at Elland Road. Chairman Ken Bates has demanded promotion this term: "Not financially, but for the fans' sake." Meanwhile, manager Grayson believes that elevation would be the perfect tribute to Gary Speed, with the club currently channelling the raw emotion from his tragic death to positive effect.
Sky Bet odds: 10/3
Having started the season in blistering form courtesy of the momentum created by last season's title charge and their move to the swish, new, Amex Stadium, Brighton then suffered a worrying stall, from which they have only just recovered. Saturday's last-gasp 1-0 success over struggling Nottingham Forest secured a third successive victory for Gus Poyet's side and retained their position in the final play-off berth. But with Blackpool, Hull City and Leicester City all within striking distance, the Seagulls are the most vulnerable of the current top six to the challenges of the chasing pack.
Sky Bet odds: 10/1