The early success of the New York Red Bulls this season has brought renewed attention to the role their USL reserve side, New York Red Bulls II, has had in developing players.

In the CONCACAF Champions League, the Red Bulls used seven players who had at one point been a part of their second team. Another two reserve-team products have seen time in MLS regular-season play. In an era where spending Targeted Allocation Money on players from abroad has taken on increased importance, the Red Bulls' ability to promote from within has been impressive, be it a homegrown product like midfielder Tyler Adams, or a performer like defender Aaron Long, who joined from outside the academy pipeline and developed in the USL.

With player development at the forefront of conversations surrounding MLS these days, and given that kind of production witnessed in New York, one would expect every other MLS team to follow the same development blueprint in terms of how to utilize its reserve team.

But looking around the league, it's clear that not every team is following suit, and some are moving in a wildly different direction. In the past two years, three MLS teams -- the Vancouver Whitecaps, the Montreal Impact, and Orlando City -- have done away with their standalone reserve teams in the USL. At this stage, Orlando doesn't even have a USL affiliate where it can send younger players needing first-team minutes. Columbus Crew SC and the New England Revolution are in the same boat after previously having affiliate agreements with USL teams. They've opted instead to loan players out on a case-by-case basis.

"I think what you see happening is the shakeout of every club analyzing what their strengths and weaknesses are, and making a decision that best suits them," said Orlando City GM Niki Budalic. "I don't think that there should be a league-wide model where everyone does the exact same thing."

The ages between 18 and 21 are a critical phase in a player's development, and it's one where in North America plenty of careers seem to stagnate due to a lack of competitive matches. That's where the USL has come in -- though the average age of players is around 23 -- providing MLS teams with mechanisms to provide players with opportunities to get valuable playing time. For some, like the Red Bulls and Real Salt Lake, that has mean fielding their own reserve teams. For others, the affiliate model is used.

After developing with the New York Red Bulls' USL reserve side, Aaron Long is prospering with the first team in MLS. Vincent Carchietta-USA TODAY Sports

Where the approaches of teams diverge often come down to the fact that not all academies are created equal. For the likes of Columbus, Orlando, Vancouver and New England, the output from the academy wasn't enough to fully stock a reserve team in the USL.

To be clear, there are extraneous reasons as well. In the case of Columbus, the uncertainly around its possible move to Austin, Texas, factored into the decision to not field a reserve team in USL. But according to manager Gregg Berhalter, the academy production was a bigger reason.

"I firmly believe that the pathway should be academy, USL, first team," said Berhalter. "That's a great pathway. I'm envious of the New York Red Bull model where they get to play great players for two years in the USL and then they can say: 'These guys are as good as we thought they are, or they're not going to make it.' But we just don't have the players to justify the expense of a standalone USL team. The number of academy kids we were able to produce every year, the number is just not great enough. Being in a small market, we have good players, but the depth of them isn't that wide. It's difficult then to say we're going to have a USL team for four players."

The affiliate model has its drawbacks as well. A USL manager's goal of winning games doesn't always align with the MLS team's desire to see its players get minutes. There was also the dynamic of the MLS players being force fed to the USL team, arriving on a Thursday for a USL game at the weekend, thus complicating the USL manager's ability to game plan.

"For us, that one-team, stronger affiliation ended up limiting our options for our players," said New England Revolution president Brian Bilello. "If we had a goalkeeper who needed minutes, but they love their goalkeeper, it created some strain there versus being able to farm out opportunities where we thought it would be the best fit for our players. So we moved away from that program and now what we do is a number of looser affiliations across the country. The goal of that is for us to match the player with the right opportunity."

The other piece is the kind of player being developed at the academy. Are they top players, contributors or bit-part players?

"For us, the academy is used to develop key contributors to the club," said Bilello. "I think if you've got a key contributor coming out of your academy, in our mind, he's playing for you when he's a teenager for the first time. There's not necessarily a lot of guys who can do that."

In Vancouver, more localized factors played into the decision to do away with the reserve team. Team president Bob Lenarduzzi cited how the presence of the second team put a strain on team infrastructure. He added that the presumed start of the Canadian Premier League will likely result in another team in the Vancouver area, making for a more crowded market. The number of players breaking through to the first team was limited, so the decision was then made to partner with USL side Fresno FC, whose GM Frank Yallop has a longstanding relationship with Lenarduzzi. Four Vancouver players are currently on Fresno's roster.

"I think the idea of being in an environment like Fresno, where they are the focus and they have to work hard to actually get some minutes with the team, doesn't hurt," said Lenarduzzi. "Would we prefer if they were closer? Yeah, but I think that we're feeling that if these players can get some minutes and prove what they can do in a good league, then when you look at your development in your club, it's a numbers game, and the ones that push through, there's not going to be that many that get to the senior team and do that well. We're hopeful that in that environment they'll thrive and that next preseason, or perhaps sooner, they'll come back and get an opportunity."

The form that the development pipeline takes for a team remains fluid. Budalic said that Orlando City will reconstitute its reserve team next year, but in USL Division III. Budalic said the lower average age of players in the league -- between 19 and 22 -- would allow the reserve team to be more closely aligned with its academy. Players that progress through that team will then be loaned out to higher-level leagues.

For New England, if a proposed USL team in nearby Hartford, Connecticut, comes online next year, as is expected, then the Revs will return to the affiliate model, albeit in a manner different than what they encountered previously.

"The Hartford model is more of an in-between where we can have more control of what's happening down there and we'll have the players in training during the week and then go down for one training session and a game," said Bilello. "They'll get that experience of training with the first team and understanding exactly what we want to do and really the competitive nature of those training environments. Going head to head with our first-team starters in training, we know that experience is going to be great for our players as well."

The danger of going for something less than a standalone reserve team in the USL is that the net isn't cast as wide, and a late-bloomer like Long might be missed. Then again, the alternatives have seen some successes. Columbus benefited from Lalas Abubakar's loan to the Pittsburgh Riverhounds last year. The same was true for New England goalkeeper Matt Turner and his loan to the Richmond Kickers.

Player development remains a hot-button issue in MLS. The ensuing years will reveal which investment decisions will pay off.