Mike Macdonald is a brilliant defensive coach – he has proven it with three teams (including the Seahawks) over the past few years. But sometimes he is too smart for his own good – or for his players’ good.

Thursday night was one of those times.

As hard as it is to fathom, his stellar defense surrendered a franchise-worst 581 yards to the juggernaut Rams. That included 457 passing yards from Matthew Stafford and 225 receiving yards from Puka Nacua.

Six Rams had receiving plays of 19 yards or more. Nacua had a 58-yarder and a 41-yard TD in overtime.

It was a big shock after the Hawks had held Stafford to just 130 yards in Week 11.

Macdonald admitted he tried to get too fancy in the game plan on a short week.

“I think we felt momentum on some of the things we were doing schematically over the last month and felt we could take a couple easy next steps – the next iteration of what we’ve built. And felt like it wasn’t that taxing on the guys.”

But it turns out he picked a bad time to expand the playbook – a short week when they took no full-speed practice reps and then had to play in front of their own raucous crowd that made it hard to communicate.

“There are some things where we asked too much of the guys,” Macdonald said. “We’re definitely going to learn from that.”

The Rams recorded seven pass plays of at least 25 yards. Macdonald chalked it up to poor fundamentals by Seattle defenders, indecisiveness at times and some third-down miscommunications.

“That can’t happen,” he said. “If we’re not executing at the highest level, it means I didn’t make it clear enough for them to go execute in those moments. That stings knowing those sometimes are avoidable.”

Macdonald also lamented the early-game failures on first down – the Rams averaged over 11 yards per play on first down in the first half.

Macdonald pointed out, “You can’t rush the passer on second-and-1.”

The Seahawks’ front finally got it going in the fourth quarter, and the unit forced three straight three-and-outs and held the Rams without a point on the final five possessions of regulation. The Hawks had pressured Stafford just seven times in the first three quarters, but they got 10 pressures on him in the fourth.

In the end, there were a lot of reasons the Seahawks were so terrible on defense for three quarters vs. the Rams — “Everybody takes part in that accountability,” Macdonald said.

But you can count on him to get it fixed for the last two games against Carolina and San Francisco – and then for the playoffs beyond that.