"We truly want to see him at the nickel spot," Davis said Wednesday. "In this day and age and the way the NFL is right now, your nickel defensive back plays more than some of your inside [linebackers]."
Boykin, naturally, wants to play all the time.
"I want to play both. I want to be on the field as much as I can," he said Tuesday. "At the end of the day, being a starting corner in the league is the highest you can possibly get. Nickel is not exactly a starter."
Last season as a rookie, Boykin played in 48.8 percent of the Eagles' defensive snaps, per Pro Football Focus. He had his struggles playing zone, but improved as the season progressed.
Davis said that having Boykin start outside only to move inside would be a challenge, "especially in the same series."
"Now in the preseason we can play him at corner in two quarters and play him at nickel for two quarters and we can get the different looks," David said. "When you start the season, to start at corner and to start at nickel it becomes more challenging. It is something that usually the older veterans can pull off."
Fletcher has started the first two preseason games at left cornerback. When Cary Williams, who is expected to start on the opposite side, sat out the first game with a hamstring injury, Davis elected to start Brandon Hughes rather than Boykin.
But Davis has acknowledged Boykin's solid performance through training camp. Fletcher hasn't stood out. That can be a positive as well as a negative. Davis said that Fletcher hasn't been "flashy," but he has been consistent.
Fletcher hasn't been a full-time starter since 2011 with the Rams. He went into that season's camp as the starter and held onto the job throughout the preseason. He said he's feeling the same vibes with less than three weeks to go until the Eagles open the season.
"Yeah, right now I feel like I'm out there, and unless things change or something changes or I'm told something different, that's the way I'm feeling now," Fletcher said.
Fletcher, 27, tore the anterior cruciate and medial collateral ligaments in his right knee during an October 2011 practice. He played all 16 games the following season, but was on the field for only about a third of the snaps in a part-time role.
When the Eagles signed Fletcher and Williams as free agents this offseason, they made note of their new corners' size (Fletcher is 6-foot, 200 pounds; Williams 6-1, 190) and the aggressiveness with which they played the position. Both were considered two of the more sure tacklers in the league. But they had liabilities in pass coverage.
Aside from Boykin, no other corner has seemingly made a run at the veterans. Hughes' ceiling is limited. Curtis Marsh recently fractured his right hand and is in danger of not making the team. Rookie Jordan Poyer has not impressed. Eddie Whitley and Trevard Lindley remain low on the depth chart.
Boykin is listed at 5-10, 185 pounds this season, a year after the Eagles had him at 5-9. He has an above-average vertical leap that was measured at 421/2 inches at the NFL combine in February 2012. Boykin said his athleticism offsets what he may lose in size.
"The coaches know that, too," Boykin said. "Otherwise, I wouldn't be out there and in the conversation. The height is not a question."
But there are other questions, according to Davis. The primary one being the Eagles don't want to have Boykin flip-flopping positions in-game. The other is that safety Patrick Chung, Hughes, and Whitley aren't ideal slot corners.
"That is a huge job that gets a lot of attention and it really is a unique skill set," Davis said. "It's not that [Boykin] isn't challenging outside, but we [want to] get the best guys on the field."
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