Both the English and Scottish champions are in live action on BT Sport this weekend, as Manchester City host Crystal Palace and Celtic travel to Dundee United.
Viewers can enjoy another feast of football, including games from the Barclays Premier League, Scottish Premiership, Vanarama Conference and leagues from around the world.
Man City v Crystal Palace at 12:45 on Saturday December 20th is the main attraction, with a win for Manuel Pellegrini's side taking them level with Chelsea on 39 points at the top of the table.
Should City claim the points, Jose Mourinho's Blues will have to wait until Monday night - when they travel to Stoke City - for the opportunity to re-establish a lead.
With home advantage at the Etihad, Man City go into this game as strong favourites, but Crystal Palace have been known to spring the odd surprise.
The Eagles have plenty of pace in attack, and managerial nous in the form of the experienced Neil Warnock. At the very least, Palace will make their opponents work very hard for the win.
The Scottish champions - and the current league leaders - Celtic travel east to face Dundee United in a lunchtime kick-off (12:15pm) on Sunday December 21st.
Ronny Deila's side are six points ahead of Inverness Caledonian Thistle, and a further point clear of their third-place hosts. A win for the Tangerines would bring them to within four points of the top, with a European place well within the realms of their capability.
But as ever, Celtic will fancy their chances of claiming three points on the road, as they look to put more distance between them and the chasing pack.
BT Sport viewers can also look forward to some non-league action this weekend, as Bristol Rovers take on Gateshead in the Vanarama Conference at 7:45pm on Friday December 19th.
These two sides - from either end of the country - are both chasing promotion this season, with Rovers currently lying in third and Gateshead just outside the play-off places in seventh.
The Pirates - whose long stint in the Football League ended last season - are desperate to escape non-league at the first time of asking.
Meanwhile their Tyneside opponents - who have a third-round FA Cup tie against West Brom to look forward to in January - are yet to play in the top four divisions in their present incarnation.
The old Gateshead AFC were members of the Football League between 1930 and 1960.
Of the other fixtures to be shown live on BT Sport this weekend, the highlights include FC Metz v Monaco from France's Ligue 1 at 7pm on Saturday, and Roma v AC Milan in Italy's Serie A at 7:45pm.
On Sunday, Inter Milan take on Lazio at 7:45pm, while Bordeaux host Lyon in an 8pm kick-off.
There's also a double-header from the German Bundesliga to look forward to, as BT Sport shows Hertha Berlin v Hoffenheim at 2:30pm and SC Freiburg v Hannover 96 at 4:30pm.