1)    *Joe Haden said this is the best defense he has ever been a part of *

Obviously, confidence is high in every NFL building in July. But Haden isn't messing around.

After the first year in Pettine's and defensive coordinator Jim O'Neil's system, the Browns defenders feel like they are putting on a pair of comfortable shoes when they trot on the football field. Graduate -level concepts have been added in the classroom to further this process.

In 11-on-11 team drills, Haden jumped a pass, batted the ball to ground, and did a little dancing jig to energize the crowd.

"Joe showed his usual form out there today," Pettine said with a small smile of satisfaction.

The defensive personnel is completely different than what Pettine had in Year 2 of his stint with the Jets, but the expectation level is creeping toward that team. That season, New York finished third in the league in total defense and racked up 25 interceptions. The tenacious way the unit played helped propel the Jets to 11 wins during the regular season.

"We definitely feel like we are the strong-suit of the team," Haden said. "If things don't go our way all the time, we want to be able to have the team lean on the defense."  

Cleveland's defense is definitely embracing the pressure, and it could be a key to the entire season.

2)    *The wide receivers are practicing with high intensity*

We'll have much more later on Terrelle Pryor, but did his arrival increase the intensity from this group? Perhaps no player looked more energized than Travis Benjamin, who is not only fighting for playing time but also a lead spot in a very crowded wide receiver room. Thursday's offensive game plan included an array of short passing play calls and Benjamin was cleaning up over the middle, using his speed burst up the sideline. 

Teammates also continue to rave about second-year Taylor Gabriel's potential.

"He's going to special," Haden said.

Rookie Vince Mayle saw his first ever 11-on-11 action, and his 6-foot-2, 225-pound size is obvious. Pettine said he may experience some soreness following his recent thumb surgery, but Cleveland wants to keep throwing his way in practice to see what he can bring to the table.

Photos: 2015 Training Camp Day 1

3)    *Alex Mack took every starting rep at center*

When the offensive linemen were called to join the running backs and receivers on the field, Mack was the first one sprinting to the ball. You can tell he's genuinely missed football since breaking his leg Week 6 last season against the Steelers. The little things the Pro Bowler does in the running game, especially on double teams, are among the best you'll see in the league.

Mack is gung-ho to get back to midseason form, but Pettine has already told his 29-year-old center there's no need to push the limit when he's already an established veteran player.

"The big part will be the communication with him," Pettine said. "How does he feel? If he needs a day, if he needs some reps, if he needs to cut some time back. He knows his body better than anybody else. We will depend on him to let us know when he does need to scale it back."

4)    *Pettine says the quarterbacks are further along this season*

Josh McCown and Johnny Manziel both made some good throws Thursday and both would like to have a few back. As noted earlier, most of the play calls were underneath throws and short passes to the running backs.

There may have been a lack of eye-popping big plays on Day 1 of camp, but there was progress in one area: grasping the offense.

"What I liked, regardless after the ball was snapped, was the command in the huddle and the knowledge of the offense and to be able to take a play and if a guy was lined up wrong and move him and just the way the play was being called and the cadence," Pettine said. "Some times that takes some time. We're further ahead this year than we were a year ago with that."

5)    *Other news and notes *

• Pettine noted the team is going to be cautious with Phil Taylor (knee) and will keep him on a pitch count during the first week of training camp.
• John Greco started at right guard while Cameron Erving ran with the second-unit.
• "If Cam wants to break into that lineup it is not going to handed to him. He is going to have to earn it," Pettine said.
• Connor Shaw continued to look like a very capable backup quarterback. He has not received second-team repetitions throughout the offseason, but he's been executing when given his few snaps.
• Practice was cut short by 30 minutes because the Browns are in the acclimation period, when players will experience more soreness during the first few days. The pads will go on Saturday. 
  
  Photos: 2015 Training Camp Roster