Antonio Brown is taking extra measures in his efforts to return to the practice field. 

Vic Tafur of The Athletic reported Saturday that the Oakland Raiders' All-Pro receiver will see a foot specialist as he looks to return to the practice field sooner rather than later. Brown, who has missed most of Oakland's early training camp practice sessions, reportedly sustained his injury before the start of camp. Brown was included in Oakland's non-football injury list at the start of training camp. 

Brown, who was cleared to take part in last Sunday's practice before being sidelined again, was not on-site Saturday as the Raiders continued to practice without him. Following practice, Oakland quarterback Derek Carr assured reporters that he is confident that he and Brown will pick off where they left off whenever Brown is cleared to practice. 

"You think every rep you miss is an important time. That's how I've always looked at it," said Carr, who threw a career-low 19 touchdown passes last season. "We wish the healing process of whatever is going on [with Brown] will be fast. But at the same time, you can't rush things for training camp when you know you have a season and hopefully a playoff run to think about. The trainers know way more than any of the players know. We just know that when he does show up, we can't wait. [We'll] welcome him with open arms and hopefully, he's healthy and ready to hit [the ground] running." 

Carr said that his offseason throwing sessions with Brown has given the duo a strong foundation that they will continue to build upon whenever Brown gets back. 

"We spent a lot of time at my house throwing. We spent hours upon hours throwing," Carr said. "So there's chemistry, there's development. I'm used to throwing him the ball. It won't be brand new when he shows up. It will just be more on him getting the details of the routes. Getting out and doing it, correcting it on film and going and fixing it the next day. Those kinds of things. But besides that, the timing aspect, the meat and potatoes, so to speak, of what we need, it's there. Just those details when he gets back, we'll iron out." 

While Brown will still be Oakland's No. 1 receiver whenever he returns to the field, Carr also spoke glowingly Saturday about two of his other, less-heralded new receivers. Carr said that he has been getting flashbacks of throwing to former Raiders' receiver Andre Holmes when throwing passes to Tyrell Williams, a former 1,000-yard receiver with the Chargers who signed with the Raiders this offseason. Williams made an impressive, toe-tapping touchdown reception during Saturday's practice. 

"Tyrell is not just a No. 2 receiver. He can easily take that featured role and be a 100-catch, 1,000-yard guy," Carr said of his new wideout. "The fact that we got him is a blessing." 

Carr also spoke at length about J.J. Nelson, a small but speedy receiver who averaged 17.8 yards per catch during his four years in Arizona. 

"The one thing you can't coach, man, is speed," Carr said of the 5-foot-10, 160-pound Nelson. "Watching him run, not only go-routes but I was — not shocked — but surprised at how well his route running was, [both] short and intermediate. Usually, those fast guys with longer strides, those short routes are kinda harder for them, those quick bursts and turns, which is a lot of coach [Jon] Gruden's offense. You gotta be a good short-area route runner, and he's been able to do it great." 

While Williams and Nelson continue to show promise in Gruden's offense, the Raiders will need a healthy Brown if Oakland is going to seriously challenge the Chiefs for AFC West supremacy in 2019.