SANTA CLARA >> The 49ers’ gaffe-per-game consistency on special teams is a glaring culprit in this season’s 3-4 start, and there’s plenty of hang time with that concern for Sunday’s visit by the Dallas Cowboys.

“We’ve been beaten a couple of different ways, and we know the reasons and the mistakes for that,” said Chris Conley, a core special-teams player. “Corrections have been made. Now it’s time to go out and put it on film.”

The Cowboys (3-3) are coming off a bye week in which they could scout openings for their elite return units. They’re averaging an NFL-best 34.2 yards per kick return and an NFC-best 19.2 yards per punt return.How bad do the 49ers’ coverage units rank? Dead last on punt returns (18.4-yard average) and 29th with a 33-yard average per kick return, the latter of which figured to be volatile with the NFL’s introduction of dynamic kickoff rules this season.

“We’ve got to get a lot better at it. It’s pretty obvious to everybody,” coach Kyle Shanahan said. “It’s obvious to us, it’s been that way for a few weeks and can’t give you guys one narrative on it, because there’s not one narrative.”

The 49ers have committed at least one special-teams gaffe in each of their past six games. They include a blocked punt, a fake punt, a missed field goal, a last-minute punt return, a fumbled kick return, two injured kickers, a 97-yard kick return for a touchdown, a 55-yard punt return, a missed point-after kick, and an embarrassing onside kick.

Special teams coordinator Brian Schneider and his assistant spent the first two periods of Wednesday’s practice hammering home details. Players responded with focus and urgency in the shells-only session.

“I’ve been on plenty of teams and it’s not coached incorrectly at all,” said tight end Eric Saubert, who’s played a team-high 115 of 180 special-teams snaps this year. “We just need to go out and execute. It’s been frustrating for sure.

“At one point,” Saubert added, “you have to make a stand and put together a good game.”

Danger lurks this game with Cowboys return specialist KaVontae Turpin, who made the Pro Bowl as a 2022 rookie and used his speedy frame (5-foot-9, 153 pounds) to rack up 194 yards on four kick returns in the Cowboys’ last game, a 47-9 loss to Detroit ahead of last weekend’s bye.

Conley called Turpin one of if, not the best, return man in the league. “He’s explosive, he has vision, he can really do it all. It’s no secret now,” Conley said. “A few years ago, people had a lot of questions. Now there are no secrets about what he’s capable of doing and the fact he can change the game.”

Added Saubert: “It puts a huge emphasis on being in the right spots in our coverage.”

Mitch Wishnowsky’s net average of 35.6 yards per punt ranks 30th in the NFL; it’s still better than the 34.4-yard net average the 49ers got from Percey Harvin III in the preseason while Wishnowsky (knee) was sidelined.

Saubert spent a week last October with the Cowboys (before joining Houston) so he’s keenly aware of the surprises special teams coordinator John Fassel typically has in store, especially against vulnerable prey like these 49ers’ units.

Cowboys kicker Brandon Aubrey missed Wednesday’s practice on jury duty, so the surprises have already begun.

In terms of their own returns, the 49ers lack sizzle, as usual. Rookie Jacob Cowing has averaged 6 yards on nine returns, none longer than 11 yards; he has made three fair catches, one at the 6-yard line. Annual reminder: The 49ers have not returned a punt for a touchdown since the 2011 season opener.

The 49ers have returned eight kickoffs through seven games, by Isaac Guerendo (three for 90 yards), Deebo Samuel (three for 73), and Patrick Taylor (two for 45), with none longer than 35 yards. Thus, the 49ers overall rank 30th in punt returns (6.2-yard average) and 20th in kick returns (26.0 average); the Cowboys’ coverage units are 29th on punts (14.3-yard averge) and 10th on kickoffs (24.7-yard average).

The 49ers’ wave of injuries has impacted the special teams.

“There’s a bunch of movement on those guys, so you just keep developing them, you keep working with the individual drills,” Shanahan said. “You can’t do all stuff full-speed, especially tackling and things like that. But we’re emphasizing everything and trying to get our group better.”