MIAMI GARDENS — Question: What’s cause for more concern, the three top Miami Dolphins receivers who keep missing practices with injury or the five starting offensive linemen who keep making them? The linemen showed up for work again Wednesday and gave the answer. It’s generally not a good thing when they’re noticeable, and they’ve received plenty of notice already this summer. It’s not time press the panic button — the idea here, in fact, is dredge up history to suggest the opposite, for this line be coached into a unit, for these expensive pieces to make it work and for this noticeable offensive line to turn efficiently invisible come the regular season. But you see plenty to wonder about now. Rookie Liam Eichenberg, who cost a second- and third-round pick this draft as a “plug-and-play right tackle,’’ as ESPN draftnik Mel Kiper Jr. said, was moved to the less-challenging position of left guard. Re-plug him there? That highlighted a shuffling of positions. And questions. They spilled into the first preseason game, when the running game started at the Chicago 1-yard line and ended two plays later at the 3-yard line. [Most Read Dolphins Coverage] Dolphins camp: Rowe shines during matchup with Falcons’ Pitts; stock up, stock down and other Wednesday observations » Then Wednesday. Dolphins quarterback Tua Tagovailoa gushed afterward about the Atlanta two-minute drill at the end of their joint practice that played tic-tac-toe down the field for a final-seconds field goal.