Stephen Curry and Klay Thompson combined for only 20 points on 8-for-27 shooting in Game 1 of the NBA Finals on Thursday, and yet the Golden State Warriors rolled the Cleveland Cavaliers 104-89 just the same. When something like that happens, there are obvious reasons: Golden State’s bench played out of its mind, and Cleveland’s offense fell in a hole. Those things will probably even out as the series goes on, but the Cavs should be more concerned that, on a night when the Warriors’ biggest guns went quiet, the holes in their defense were already glaring.

Coming into the series, the basic bargain of this season’s Cavaliers compared to last year’s was an improved offense producing enough to cover for an inferior defense. The Cavs’ shots didn’t fall in Game 1 as often as they normally do, and a lot of the shots that went in for the Warriors’ bench were absurdities — Leandro Barbosa fading away to his weak-hand baseline isn’t on the scouting report. But Kevin Love and Kyrie Irving, the two Cleveland stars playing in this series who combined to miss all but one game of last season’s Finals, were worked over exactly as expected.

On 18 shot attempts in which Irving was the nearest defender, the Warriors had an effective field goal percentage (eFG%) of 66.7, according to data from the NBA’s player-tracking cameras. On the 13 shots in which Love was the nearest defender, the Warriors had an eFG% of 61.5. Both of those numbers are very bad. There’s some margin for error on these plays — for instance, the cameras will sometimes assign a “nearest defender” who is guarding a different offensive player because the shooter’s defender was so badly lost — but the underlying plays looked just as terrible.

During the regular season, Love gave up 90.3 points per 100 chances as a pick-and-roll defender, which isn’t good; in the playoffs, he’s given up 102.9, which is a calamity. On Thursday night, his screen-and-roll defense came out to 94.1 points per 100 chances, and that’s in the context of Curry and Thompson playing awfully — it’s a bad sign of things to come. The Cavs’ plan for Love defending the pick-and-roll — a big concern before the series — seemed to be having him double-team the ballhandler. But traps only work if you can actually trap the player, and Love’s attempts at doing so led to plays that looked like this:

Or this:

The Cavs might need to rethink this strategy.

Meanwhile, Irving was taken down to the block when he switched onto one of the Warriors’ bigger wings, was back-cut when he lost his man while watching the ball, and was run through screens away from the ball to free up shooters — all stuff we figured would happen this series, but again, a bad sign when it happens with Curry and Thompson out of the picture.

This has been a playoff-long swoon for Irving, as well: In the regular season, he allowed shooters an eFG% of 50.5; that’s ballooned to 59.2 in the playoffs.

Cleveland’s offense had its own problems — in 22 possessions, Andre Iguodala held LeBron James to 1-for-2 shooting — but it’s still a good bet that it’ll course-correct. The bigger concern for the Cavs is that any gains they make from improved shooting will drain out of the holes in their defense.