JACKSONVILLE – It was a good start, if not a great one.

That was Jaguars Head Coach Gus Bradley's assessment of Day One of 2016 Organized Team Activities Monday, the first day of the on-field practice portion of the offseason program.

It also for the Jaguars was a day for catching up on offseason injuries, with Bradley announcing that defensive tackle Sen'Derrick Marks will not participate in OTAs and that center Luke Bowanko and defensive end Jonathan Woodard will be placed on the Physically Unable to Perform list.

The Jaguars worked for about an hour and a half Monday.

"There were some issues we need to get taken care of, but I kind of like that for the first day," Bradley said late Monday morning. "The team recognized it. What I saw that I did like was that we're holding each other accountable from Day One. Those guys know the standard.

"Overall, there were some good signs. I think the young players are holding us back a little bit, but that happens at this stage."

Bowanko, a third-year reserve offensive lineman who started 14 games at center as a rookie in 2014, sustained a labrum tear in his right hip that will require surgery.

Woodard, a defensive end selected by the Jaguars in the seventh round of the 2016 NFL Draft, has undergone surgery to repair a torn Achilles tendon sustained recently in Phase Two of the Jaguars' offseason program.

Bradley said he was pleased with OTA attendance, with all veterans participating in the voluntary period.

"A coach called me and said, 'Gus, don't take that for granted: you could have 10 or 15 guys not show up,''' Bradley said. "I don't take it for granted. It's awesome. Our guys are incredible that way. They line up, go to work and I appreciate that.''

Also Monday:

*Rookie cornerback Jalen Ramsey did not attend practice. He is seeking a second opinion on the small tear in his right meniscus sustained in Phase Two of the offseason program. Bradley said Ramsey sustained the injury in a workout, completed the workout, and then told the team later he was experiencing discomfort in the knee. "You really can't see anything on tape," Bradley said of the injury to the No. 5 overall selection in the '16 draft. …

*Rookie linebacker Myles Jack, the Jaguars' second-round selection in the draft, also did not attend practice. He will not participate until mid-June because his college, UCLA, is still in classes at that point. NFL rules prohibit rookies from participating in an offseason program until the end of the school year…

*Bradley said Marks will not participate in OTAs. He missed the last seven games of last season with a torn triceps and missed the first five games after rehabilitating a torn anterior cruciate ligament sustained in the 2014 regular-season finale. …

*Bradley said defensive end Ryan Davis will work at the Otto, strong-side linebacker position after working primarily at Leo pass-rushing defensive end the past three seasons. The team is working to develop a "Lotto" type position with traits from the two positions, with Otto Dan Skuta also involved in that position. …

*Third-year tight end Blake Bortles participated in practice with a broken hand. …

*Cornerback Prince Amukamara, wide receiver Blake Bortles (hamstring) and linebacker Thurston Armbrister worked on the side on Day One, with defensive tackle Roy Miller not participating in practice. Wide receiver Blake Bortles also is among the veteran players with whom Bradley said the team will be "cautious" during OTAs. …

 *Josh Wells, the No. 2 overall selection in the 2013 NFL Draft and the starting left tackle the past two seasons, worked at tackle and guard Monday, Bradley said. Joeckel is expected to compete for the left tackle position in training camp with free-agent signee Kelvin Beachum, who will miss OTAs rehabilitating a torn ACL. "He looks stronger," Bradley said of Joeckel "He's really focused. He looks like a different kind of player. Not that he wasn't before, but he's on a little bit of a mission, it feels like." …

*Bradley said cornerback Jalen Myrick has been among the standouts in the offseason program. The third-year veteran will miss the first four games of the regular season for violating the NFL's policy on performance-enhancing substances. "His work ethic, his attitude … he's doing really well," Bradley said. "If you were to say, 'Gus, who's standing out in Phase One and Phase Two?' Aaron Colvin. I'm not concerned about his spirit. He's disappointed this happened, but it's not affecting his work ethic."

*Bradley said second-year veteran Neal Sterling has been moved to tight end after being a wide receiver as a rookie. A seventh-round selection in the 2015 NFL Draft, Sterling has size (6-feet-4, 240 pounds) and speed to play the move tight-end position. "All the skillset we're looking for that is not a problem for him," Bradley said, adding that in-line blocking will be the area Sterling needs to improve at the new position. …