Offensive Coordinator Mike Sullivan is preparing Geno Smith to start for the Giants Sunday against the Oakland Raiders:

EAST RUTHERFORD, N.J. –Mike Sullivan has spent more time working with Eli Manning than any other coach on the Giants' staff. So to Sullivan it was a major transaction when it was announced that Manning would not start on Sunday in Oakland, ending a 13-year streak of 210 consecutive regular-season games.

"Tuesday," Sullivan said today, "obviously was a very difficult day."

That's the day the Giants announced that Manning's streak will end Sunday in Oakland, where Geno Smith will make his Giants start for the team against the Raiders.

Sullivan is the team's offensive coordinator, and is tasked not only with formulating the game plan with head coach Ben McAdoo, but working closely with Smith to ensure that he has the best chance to succeed. As always, he is fully immersed this week in doing all he can to help the Giants win. But it would be inaccurate to say Sullivan is not also thinking about Manning.

Sullivan was the Giants' wide receivers coach the first six years of Manning's career. He was Manning's position coach in 2010-11, and again in 2015, and is in his second season as the offensive coordinator. No current coach has worked with Manning longer, or in more capacities, than Sullivan.

"Eleven years," Sullivan said. "Worked closely with Eli as a member of this coaching staff, as a receiver coach, quarterback coach, the coordinator, and then these past few weeks being able to call the plays for him, and so many experiences that we shared together. The highest of highs – a couple Super Bowl trophies. The lowest of lows, you know, I think you could certainly say this season has had its fair share of those. And everything in between and the thing is, through it all, he has been the ultimate professional. He personifies class and humility, toughness, competitiveness. I just have great respect for Eli Manning as both a player and as a man and over that long period of time, we developed quite a bond – a strong bond – and there's nothing that can take that away or break that bond."

Because the Giants are 2-9, team president John Mara, McAdoo and general manager Jerry Reese deemed it important to play both Smith and rookie Davis Webb in the season's final five games so the team can have a more complete evaluation of them entering the NFL Draft. The decision did not change Sullivan's weekly routine.

"It's more a matter of what are my responsibilities, and the responsibility being that there is a group of players, there's a quarterback that needs direction and we've had so many struggles this season," Sullivan said. "It's been very, very difficult, so I think it's really trying to zero in on trying to find a way that we can get this thing headed in the right direction. It's been frustrating, obviously, for everybody. So that's where the focus is, and trying to get this unit ready for a game in Oakland."

Smith, who joined the Giants in March, has thrown just two passes this season as the No. 2 quarterback. But Sullivan was impressed with his work in training camp and preseason games, and he believes Smith has the attributes to succeed in his new role.

"The big thing in terms of Geno … he has arm talent," Sullivan said. "He has a very live arm and he's got mobility to extend some plays. … Geno has worked hard all year and done the things that you want someone who is the No. 2 quarterback to do in terms of preparation and really zeroing in on doing all the things necessary that if he does get the opportunity, he'll make the most of it. He's obviously excited about the opportunity. It's a chance for him to show what he can do, and he's looking forward to what happens on Sunday."

Webb is not expected to play Sunday – Manning will be the No. 2 quarterback – but McAdoo said he will see action before the season ends. The rookie was inactive for each of the first 11 games.

"In terms of what Davis has done offensively, you go back (to) the preseason and training camp and him being involved in that aspect of it," Sullivan said. "As the regular season has gone on, he's been primarily in the scout team role and as far as what happens in the future, again, that will remain to be seen."

This week it's been Manning taking many of the scout team snaps, an unusual sight after his long tenure as the team's starter. But Sullivan said he has approached that task with the same diligence which he has always applied to his job.

"He's the ultimate professional," Sullivan said. "He's the ultimate team player and while certainly not something - as he shared with everybody - a decision that he was thrilled with, he's going to do everything he can to help the team. He's preparing himself as best he can as though if he gets an opportunity, he'll be ready to go and keeping himself sharp. His attitude has been one of being a good teammate and wanting to do everything he can to help the offense, help the other quarterbacks, help everybody get ready as best he can."

*Linebacker Jonathan Casillas (neck/wrist) and defensive tackle Damon Harrison (elbow) were the only Giants to miss practice today.

Offensive lineman Justin Pugh (back) returned to practice on a limited basis. Linebacker B.J. Goodson (ankle) was also limited.

Linebacker Calvin Munson (quad) and wide receiver Sterling Shepard (illness) were full participants.