Barcelona have seen a shift over the last decade from producing consistent, exceptional young talent from their academy to signing big-money, exceptional talent—both established and up-and-coming—from elsewhere in the transfer market.

The likes of Luis Suarez and Neymar were signed for huge sums as clear world superstars, while others in the current side, such as Marc-Andre ter Stegen and Samuel Umtiti, were brought in on deals that reflected their potential for the future.

Sometimes, though, they've also managed to snare a handful of deals whereby the player they've brought in has ultimately been worth far, far more than they've paid for them, whether because of immense improvements, longevity in the side or value to the team that goes beyond mere financial outlay.

Here's the best transfer work by the Catalan club over the last decade, in terms of bringing in players way below their eventual worth.

Purely for consistency, all reported fees are from Transfermarkt.

6. Jordi Alba, £11.9M

In 2012, after an insane showing at the European Championships with Spain, Barcelona made their move to bring back Jordi Alba from Valencia.

The left-back had been in the youth setup at La Masia early in his youth career before rising to prominence with Los Che. He signed for Barca midway through Euro 2012, scoring in the final with a trademark surging run from deep that has gone on to become a hallmark of his—though perhaps not with a goal at the end of the run, more often than not.

Productivity in the penalty box aside, Alba has been a mainstay of Barca's back four for each of the five years he has so far spent at the Camp Nou, providing a speedy thrust down the left wing as an outball and an overlap option for the team as well as the ability to sprint back and recover defensively.

With around 200 appearances for Barca to his name already, three league titles wrapped up and a Champions League medal, too, the fee of less than £12 million was clearly a bargain.

Alba remains a first choice for Spain on the left and is a regular starter for Barca, though the recent switch to three at the back for Luis Enrique has momentarily stalled Alba's absolute dominance of the flank.

5. Denis Suarez, £2.8M

The signing of Denis Suarez less than a year ago brought an end to the midfielder's jaunt around Europe, which had taken in the likes of Manchester City, Barca's B team, Sevilla and Villarreal since he initially left Celta Vigo in 2011.

When Barca signed him on a free from English outfit City, it was always with the intent of bringing Denis through the system, but his two-year loan at Sevilla was soon cut short. It was last season, at Villarreal on a permanent deal, where his abilities began to shine through in La Liga, and the regularity of being in the first XI made it clear Barca should exercise their buy-back clause and indeed the wisdom of putting one in place originally.

Denis hasn't yet established himself as a starter at the Camp Nou, but he has the qualities to be handed further chances in the coming couple of seasons.

Merely being part of the first-team setup means his standing in the football world will continue to increase, and whether he goes on to be a first XI player or not, his next move is likely to be for at least six times the fee that Barca shelled out: a mere €3.5 million or less than £3 million.

It was a smart investment, potentially adding a regular squad member to the talent pool at the club but certainly securing a big sell-on fee a few years down the line if not.

4. Yaya Toure, £7.7M

Turn the clocks back to the start of the 2007/08 season and Frank Rijkaard was in his final season in charge, hoping to improve on the previous campaign's second-place finish in La Liga.

It didn't happen, with Barca ending third, but in the push to improve, there were a few new recruits who would go on to play a big part in the club's future: Thierry Henry and Eric Abidal from afar, and Pedro Rodriguez promoted from the youth team.

Additionally, Yaya Toure joined from AS Monaco, and the signing of the midfielder, though not a long-term member of the team, proved a tremendous decision.

Yaya joined for just under €10 million, in the £6.7-7.7 million range at the time, and enjoyed three years at the Camp Nou.

He was generally a central holding option under Rijkaard, later a more offensive presence under Pep Guardiola who deputised as a centre-back in emergencies and was then offloaded to Manchester City at a huge profit—around a £26 million sale.

Toure's quality has been proved over the last decade, at Barca and beyond, and he proved a wise addition at half the price or less of most of his team-mates brought in around the same time, including Alexander Hleb, Martin Caceres and Dmytro Chygrynskiy.

3. Ivan Rakitic, £15.3M

Back to the present squad and a key member of the team in Ivan Rakitic.

The Croatian joined from Sevilla in 2014, and even in the reasonably short time he has had at the Camp Nou, the £15 million fee looks an absolute bargain. Of course, Sevilla themselves secured Rakitic on an even better deal, less than £2.5 million in 2011 from Schalke, but Barca, in turn, could have easily enjoyed a profit of £30 million or so had they chosen to cash in on the midfielder.

A regular alongside Andres Iniesta in midfield, Rakitic initially helped the transition from a possession-oriented style to one where Lucho ensured the forwards received the ball as early as possible, with Rakitic's runs from deep, link play with Luis Suarez in particular and willingness to get into the box incredibly important to the team's style in his first season.

While plenty of signings (Denis, Arda Turan, Andre Gomes to name a few) have arrived since then to challenge Rakitic for a place, he remains the best and most consistent option for the team and still shows himself to be among Europe's elite with enormous performances from time to time.

Just last month, Barca signed Rakitic up to a new deal until 2021, upping his release clause to €125 million in the process.

2. Javier Mascherano, £17M

While Rakitic was slightly cheaper and may be a more rounded midfielder, he can't be seen as a better purchase than Javier Mascherano.

The Argentinian destroyer is of incredible importance to Barcelona, having shifted from defensive midfield to centre-back since signing from Liverpool in 2010 and at times being a one-man line of defence holding the team together.

With the natural emphasis on the team being one of attack, Mascherano brings balance, discipline and organisation to the side, with his leadership on the pitch being matched by his commitment to the cause and willingness to put his body on the line.

In almost seven years at the Camp Nou, he has won 11 major honours, has played more than 300 matches...and scored one goal, a recent penalty against Osasuna at the end of April.

A captain of the team whether he wears the armband or not, he has already provided so much service and top-quality performances that even if Barca had paid double the £17 million fee, he still would have been good value.

1. Gerard Pique, £4.25M

Top of the charts is Gerard Pique, and that's by whatever metric is used: low initial cost, longevity in the team, ceiling of ability or difference in signing fee to current market value.

After four years at Manchester United, Pique came "home" when Barca swooped to sign him for under £5 million, perhaps a 10th of what he might fetch now after since winning almost 100 caps for Spain, six Liga titles and three Champions League medals.

Now in his ninth campaign, only twice has he ended the season with fewer than 40 appearances to his name, and Pique is one of the first names on the teamsheet for any match with relevance or importance.

His reliability has increased year on year, his favouritism among the Barca fans is returned by way of his absolute disregard of anything to do with the team's rivals, and his habit of storming forward from central defence, to try to impact at the attacking end, is an endearing trait of the now-30-year-old that showcases his must-win attitude.

As far as steals go, his near-400 games for the club work out at somewhere approaching £10,000 per appearance, quite the astute return.