It took Wes Welker three NFL seasons and a fortuitous trade to become a game-changing prototype.

Welker was an undrafted rookie whom the San Diego Chargers cut after Week 1 of the 2004 regular season. He gained some traction with the Miami Dolphins before his career shot upward with a trade that sent him to New England in 2007.

From there, the 5-foot-9, 185-pound slot receiver became one of the game's most prolific pass-catchers. Welker made five Pro Bowls and recorded 110-or-more receptions five times over the next six seasons with coach Bill Belichick and quarterback Tom Brady.

“They were one of the first offenses to use the slot receiver on first and second down, where most offenses were doing it just on third down,” Welker, 38, the 49ers’ first-year wide receivers coach, said on the 49ers Insider Podcast.

“And really being able to take advantage of defenses that would stay in base personnel and basically try to match me up on a linebacker. New England always did a great job of trying to find those matchups.”

The game has changed over the past decade, as teams are not relying solely on a Welker-esque body type to be their slot receiver. Sure, the 49ers have Trent Taylor, who regularly draws comparisons to Welker, but the club also has Jordan Matthews (6-3, 215) running routes from the slot.

“There are certain quarterbacks that like more quick, in-and-out-of-breaks, sitting in the hole, that type of deal,” Welker said. “And some quarterbacks just like bigger targets. There are different ways, depending on what your scheme is and what the quarterback likes.

“And then also a lot of it is just having a smart guy that understands coverages and how to attack it, then using his skill set, whether it’s more bodying guys up and shoulder-punching through, or using quickness and acting like you’re breaking out and breaking in. I don’t think there’s a right or wrong way to it. You see both sides of it.”

Welker said he has yet to formulate a solid opinion on which style of slot receiver that 49ers quarterback Jimmy Garoppolo prefers, but he’s leaning toward the smaller, quicker player.

Welker said the 49ers’ passing game has a lot of flexibility because of the number of players who are capable of lining up in the slot.

“We have a lot of guys who can do it,” Welker said. “With all the formations and the way we move people around, I think it can be a lot of guys. I don’t think it’s just limited to Trent.”

Taylor had 43 receptions as a rookie – the same as tight end George Kittle in 2017 – before struggling with a back condition last season. Welker has been impressed with what he has seen from Taylor during organized team activities on the team's Santa Clara practice field.

“He’s been one of the bright spots in the spring and doing a really good job of winning on those choice routes and really understanding coverage and space and doing a really nice job out there,” Welker said.

Veteran addition Jordan Matthews has been impressive this spring, as he gives the 49ers a different body type out of the slot. Matthews, 26, registered eight touchdown catches in both of his first two seasons before being limited with injuries over the past three years. He signed a one-year contract with the 49ers in the offseason.

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Welker also mentioned Richie James, Marquise Goodwin and Dante Pettis as returning players who can run routes from the slot. The team also expects to have the option of using rookie Deebo Samuel in the slot.

“The more guys you can have that can play all over the field, and we can formation people up, and do different things, can put the defense in more conflict,” Welker said.

Wes Welker is once again making an impact on the football world.

The two-time All-Pro wide receiver was recently added to the 49ers' coaching staff as a receivers coach -- and he isn't wasting any time working with newly drafted wide receiver Deebo Samuel.

In the second week of the team's OTAs, Welker was mic'd up as he worked with the former South Carolina wideout and the rest of the team.

"I don't know whether to commend you for the swag you got going on, or fine your a--," Welker said to receiver Kendrick Bourne in the 49ers' latest edition of 'Mic'd Up.'

Perhaps both? Welker didn't appear to hold back with any statements he was making toward members of the team.

Welker, a 12-year veteran receiver in his own right, even ran a few sprints with Samuel. Dare I say he's still got it, even after his retirement. 

The 49ers were starving for another wide receiver to pair up with Dante Pettis. Coach Kyle Shanahan was rather impressed with Samuel at the Senior Bowl and despite not being the tallest guy out there, Samuel has the ability to get open quickly, according to Matt Maiocco's scouting report.

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If you want to be the best, sometimes you have to learn from the best -- especially if it's someone like Welker who will let you know when the work is done.

The 49ers' third-round selection, wide receiver Jalen Hurd is not lacking in confidence stating that there is no one else like him in the league. 

“I’ve been in the slot, I can play on the outside, obviously I have a running back background,” Hurd said. “So, there’s not really any limit to me on the offensive side I’d say.” 

Hurd is unusual for many reasons. He started playing football as a young running back but after three years at Tennessee, he transferred to Baylor and switched over to play wide receiver. At 6-foot-5 and weighing 230 pounds, he is a big-bodied receiver that the 49ers have been missing. 

Coach Kyle Shanahan has already described multiple ways he has thought about using Hurd on the offense. The specifics have not been revealed to the rookie receiver, he’s just ready to get to work. 

“I’m a mismatch guy so wherever they best see me fit, I can make a play,” Hurd said. “I can do a lot. That’s not really my position right now to guess and see where I’m going to play. I’m just going to go in there, work hard and see where I end up.” 

Shanahan sees him predominantly at wide receiver but is excited to see where he can take advantage of an opposing defense. 

“He can do about everything,” Shanahan said. “We plan on him coming in and being a receiver and working him with that group, but I don’t think that’s where it stops. We will see where his body ends up being here over the years and while he does it, we hope we can give him a few carries here and there.”

Hurd was very complimentary about Shanahan’s offensive scheming abilities and will play wherever his head coach sees fit. 

“I want to play receiver but I’m open to playing anything,” Hurd said. “He’s got a great offensive mind and I could not be more happy to be drafted and get a chance to play and just experience it so I’m looking forward to it.”  

In the middle of his third season as a Volunteer, Hurd transferred to Baylor and made his switch to wide receiver. He has stayed mum on details of his departure from Tennessee, keeping that between himself and the teams who interviewed him through the draft process. 

The position change gives Hurd a unique perspective that left him unable to offer a comparison to a player currently playing in the NFL. When Hurd’s plan was to become an NFL running back, however, a player he admired was Eddie George. George at 6-foot-3 and 235 pounds had a very similar body shape to what Hurd had entering college. 

“I was a running back so I looked at Eddie George, from Nashville,” Hurd said. “Grew up a Titans fan so there you go. He’s also pretty tall and pretty big as well.”

On the other side of the size spectrum of players is 5-foot-9 receivers coach Wes Welker. Hurd is significantly impressed by his accomplishments and can’t wait to learn from the All-Pro wide receiver. 

“Oh man, I think I read he was 18 in all-purpose yards in the entire NFL,” Hurd said. “If there’s anybody that’s done it and been successful in this league it’s him. Anything I can pick up from him, receiver and all the different roles that he did.” 

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As far as Hurd’s health, he has recovered from a minor knee procedure that he had in December which kept him from running at the NFL Scouting Combine. 

"Knee is good, I’ll be ready to go.”