Anyone who follows the English Premier League knows it has coughed up two big stories, so far this season.

–The rise of Leicester City.

–The fall of Chelsea.

The former, last season, nearly was relegated (sent to the second division) before a sprint to the finish raised them to 14th place in a 20-team league.

The latter, last season, won the Premier League and led nearly the whole way.

Now, their situations are turned upside down, and when they played tonight the bizarre new reality was reinforced when Leicester City won 2-1.

This is beyond odd because …

… the Premier League pretty clearly is the most competitive of the planet’s leading major soccer leagues, but even then, a team doesn’t go from “survivor” to “leader” in the course of one year, and neither does another go from “champ” to “chump”.

But both have happened, and most fans of the league, aside from those who support Chelsea, applaud this concept because more and more leagues (see: Spain, Germany) seem to be calcifying, in terms of standings, with the same one or two teams winning every year — because they outspend everyone else. And those who tend to finish just behind them tend to come from the same small group.

Any outsider which does well, or perennial leader which declines (Chelsea, one point above the relegation zone) … tends to amuse and interest fans.

To give you an idea of how little things change in elite club soccer, Leicester City was a 2,500-to-1 long shot to win a championship before the season, and there they are, sitting atop the league, ahead of Arsenal and the two Manchesters, as the halfway point of the league approaches, in only their second year in the Premier League after a decade in the second division.

How is this possible?

It turns out Leicester identified a couple of elite scorers, in Jamie Vardy and Riyad Mahrez. Vardy has 15 goals this season and set a record by scoring in 11 consecutive matches, and Mahrez has 11 goals. Chelsea, collectively, has 18 goals.

Leicester also has a fine coach, in the Italian Claudio Ranieri, who has coached many of the planet’s biggest clubs but came into the season as what the British call a “nearly man” — someone who can hang around in a competition but never quite seals the deal … but now is being lauded for taking this club to unexpected heights.

Ranieri and his team have been mostly brilliant, aside from a 5-1 spanking at the hands of Arsenal.

Meanwhile, Chelsea.

Their defeats early on seemed like huge accomplishments by the opposition, against a side that was so good a year ago, with a lively attack led by player of the year Eden Hazard and the vile (but often productive) Diego Costa, as well as a defense that seemed able to pitch a shutout any time coach Jose Mourinho felt like “parking the bus” in front of goal.

But now, all sorts of people have beaten Chelsea (Bournemouth, Stoke City, Crystal Palace, etc.), which almost overnight looks larded with old, creaky, detached and dispirited players.

After this one was over, Jose Mourinho, one of the most colorful and contentious coaches in the game and, until this season, a serial winner, said his players had betrayed him by not paying attention to his game plan — which warned of maneuvers that led to the goals by Vardy and Mahrez.

He also said he hopes owner Roman Abramovich, the Russian billionaire who bankrolls one of the biggest-spending clubs in the world, will keep him on as coach.

Going forward, we wait to see if Leicester City can continue on to one of the most astonishing championship runs in English history … and to see if Chelsea can recover (or be competitive in the Champions League round of 16) — and if Jose Mourinho will be there to see it.