They say that decisions even themselves out over the course of a season, but how Paul Lambert must wish that karma had waited slightly longer than four days before it redressed the balance.
Aston Villa were beneficiaries of a contentious penalty at the Emirates Stadium last Saturday, but they were denied a point at Stamford Bridge on Thursday morning (Singapore time) when a cast-iron call went unnoticed.
John Terry's injury-time hand-ball was clear to most in the stadium. Not, however, to referee Kevin Friend.
Now that the Premier League has installed cameras to confirm whether or not the ball has crossed the goal-line, the calls for the further use of technology will intensify. This is the thin end of the wedge.
When quizzed on "the apparent penalty", Lambert laughed coldly.
"Apparent?!" he scoffed.
"It's hand-ball, it's there for everyone to see."
This was not the only complaint from Lambert. He was just as frustrated that Branislav Ivanovic was still on the pitch to score the winning goal when he felt he should have been dismissed for an apparent elbow on Christian Benteke.