They both play in red and white, are both heading to promotion glory and are both stalwarts of the South Yorkshire football scene - but now Sheffield United and Doncaster Rovers have something else in common.
Supporters have noted that the two clubs, leading League One and League Two respectively, have virtually matching records with just nine games of the season left to go.
For Blades and Rovers fans, a glimpse at the league table is a pretty rewarding task right now - bit look more closely and you will see that the Bramall Lane and Keepmoat Stadium sides are locked in a head to head to battle at the top.
Both have played 37 games, and both have won 22, both have drawn nine and both sides have lost six.
And the uncanny similarities down end there. Needless to say, both are currently sitting pretty on 75 points and they've even scored the same number of goals - 71 - a figure that makes both sides the top scorers in the top four divisions in England.
And when it comes to goals against, once more, the figures are virtually identical although Blades currently have the slight edge - having conceded 42 goals to Rovers' 43.
Whether the pair have identical records at the end of the season remains to be seen, but one thing is for certain, it looks set to be a cracking season for the two sides with both now firmly in the driving seat to lift their respective league titles come May.