Sunderland spent eight of the nine seasons in the Premier League, 2009/10 to 2016/17, and the last outside it. They played City 16 times and won four. All four were at home. All four finished 1–0. And they came in four straight seasons: Darren Bent’s stoppage-time penalty in August 2010, Ji Dong-won’s last kick on New Year’s Day 2012, a Boxing Day winner in 2012, and another 1–0 in November 2013.
Add three draws and Sunderland took 15 points off City. Take City out and all 15 come off.
That is the cost of beating City. Sunderland never climb beyond City’s place. In three seasons they finish lower than they really did: 13th, not 10th, in 2010/11; 14th, not 13th, in 2011/12; 16th, not 14th, in 2013/14, two points clear of the drop and the last club safe. In the other five they move up one, and that place is City’s.
The fate never changes. Sunderland stay up in every season they really stayed up, and in 2016/17 they go down either way.