JACKSONVILLE – Nic Jacobs didn't expect this. Not quite.

Whatever his expectations, the reality is Jacobs is likely going to do more than just play for the Jaguars in San Diego on Sunday.

Jacobs, a rookie, signed with the Jaguars off the New Orleans Saints' practice squad on Tuesday. Because of the Jaguars' numbers at tight end, there's not only a chance he will play extensively Sunday, there's a real chance he may start.

That's a quick turnaround, and one Jacobs said he is embracing.

"I would say it was a very whirlwind week for me," Jacobs said Friday as the Jaguars (0-3) prepared to play the San Diego Chargers (2-1) at Qualcomm Stadium in San Diego, California, Sunday at 4:05 p.m.

"I'm picking up the offense way better than I expected to. I really feel comfortable."

Jacobs' status became clearer Friday with the release of the week's final injury report.

While the Jaguars' roster overall is healthier than it has been all season, the tight end position remains down in numbers, with Mickey Shuler ruled out with an illness on Friday.

With Shuler out, veteran Marcedes Lewis on the injured reserve/designated to return list and Marcel Jensen having been released and re-signed to the practice squad, Jacobs and fifth-year veteran Clay Harbor are the lone healthy tight ends on the roster.

"It keeps changing," Harbor said Friday of the tight end position.

Jaguars Head Coach Gus Bradley on Friday confirmed that Jacobs will be active.

"It's an interesting deal coming in with only three or four days of preparation," Bradley said. "Just my first meeting with him he appeared to be really sharp, thought he could pick things up really quick, but it's different when you go through practice.

"I give him credit for what we're asking him to do. He seems to have a pretty good grasp of it."

Jacobs, who signed with the Saints shortly after the May NFL Draft as a free agent from McNeese State, caught 32 passes for 453 yards and four touchdowns last season after transferring from Louisiana State. He spent the preseason with the Saints, and was signed to the practice squad September 1.

"It's tough," said Harbor, who joined the Jaguars off waivers from Philadelphia a week before the 2013 regular-season opener. "He's been here a week. I go back to last year. I was in a similar situation, coming in and having to play right away. It's not easy. He's done a good job studying and picking up the offense, but there's only so much you can do in a week's time. I'm trying to communicate with him and help him when he's on the field."

Because Jacobs signed off another team's practice squad, he must be on the Jaguars' active roster for at least three games. While Jacobs said he knew he would be active, he didn't expect quite so large a role immediately.

"I expected to be playing on game day, but I didn't expect to be possibly starting," he said. "My thought was I'd come here and do special teams the first week, then learn the offense. But from the looks of it, they needed me right then and now, so I had to step up and learn the offense.

"It was a whirlwind week, but it's the opportunity of a lifetime."

Harbor, who caught 24 passes for 292 yards and two touchdowns in 16 games for the Jaguars last season, has been out since early training camp with a calf injury. He practiced full every day this week and said Friday he feels full-go for Sunday.

"I'm going to go play and do my best to stay on the field as long as I can," Harbor said. "My wind's feeling good. I'll try to take care of the body and get the calf feeling better. Hopefully, God willing, I'll stay healthy and have a good game."

Said Bradley: "That's the challenge, how to really have those two work hand-in-hand. Clay really felt good this week. His conditioning – we felt he did really well, no issues, no pain or anything like that, so he's good going into the game."

Also around the Jaguars Friday:

*Fullback Will Ta'ufo'ou worked full and was listed as probable on the injury report with an ankle injury. He had missed practice Wednesday and Thursday, but ran and did special teams work Friday. "These next two days will be big," Ta'ufo'ou said. "The progress has been positive." …

*Rookie wide receiver Marqise Lee missed a third consecutive practice with a hamstring injury and was officially ruled out for Sunday. Bradley said Lee could begin running next week. …

*Defensive tackle Sen'Derrick Marks missed practice Friday with a veteran day off and is expected to start Sunday. …

*Bradley said he expects Cecil Shorts III and Allen Robinson to start at wide receiver Sunday with rookie Allen Hurns the third receiver. …

*Right tackle Austin Pasztor likely will be a game-time decision, Bradley said. Pasztor, out since Preseason Week 2 with a fractured hand, worked full for a second consecutive week but his status remains uncertain. He had been working with a club on his hand, then worked with a lighter protective device Friday that allowed his fingers more freedom. "We'll see how that benefited him today," Bradley said, adding that if Pasztor does play it will be as a backup. …

*With Sam Young starting at right tackle for Pasztor, Bradley said rookie tackle Josh Wells will play the role of an extra blocking tight end if needed. …

*Cornerback Alan Ball (abdomen), running back Toby Gerhart (ankle), Hurns (ankle), defensive tackle Roy Miller (ankle) and linebacker Paul Posluszny (ankle) all worked full Friday and are probable for Sunday. …