The Champions League is a competition that defines careers. A few good performances on the biggest club stage in Europe can enhance a player's reputation, get them a new contract, or even attract a host of scouts from opposing teams.

Over the years we have been blessed to see the likes of Lionel Messi, Cristiano Ronaldo and Kylian Mbappe blossom. But every new season in the Champions League brings new players who are able to increase their levels of performance.

With the memories of April's failed attempt by 12 clubs to form a breakaway European Super League still fresh, the 2021-22 Champions League group stage is proof that you don't need to mess with the competition.

So here are 11 players who have made the step up to shine this season. Some of them are already well established at their current clubs, but their contributions in Europe have taken them to another level.

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Goalkeeper: Georgios Athanasiadis, 28, Sheriff Tiraspol

Sheriff's incredible 2-1 win over Real Madrid at the Bernabeu in the Champions League group stage would certainly not have happened without a string of magnificent saves from the Greek goalkeeper, and the one which denied Luka Modric from close range late in the second half was especially outstanding.

A loan signing from AEK Athens this summer, Athanasiadis faced an incredible 28 shots in the Spanish capital, of which 11 were on target, and did brilliantly to keep Madrid at bay. He also proved decisive for the Moldovan minnows in their qualification for the group stage as he kept two clean sheets against Dinamo Zagreb in the playoffs. Excellent on the line, agile for his size and equipped with wonderful reflexes, he's a traditional shot stopper who thrives under pressure.

Right-back: Rasmus Kristensen, 24, FC Salzburg

Having struggled with the step up from FC Midtjylland when he joined Ajax in 2019, the Denmark international left after 18 months and has blossomed in Austria. Due to his centre-back-esque build, Kristensen can be hard to assess at first, but once settled into the pace of a game he catches the eye with strong forward runs, a decent touch and ability to navigate narrow spaces. He is also able to get himself into the position to put in a cross.

Central defender: Goncalo Inacio, 20, Sporting CP

Quick, agile, aggressive and adventurous going forward, the 20-year-old only made his debut for the Portuguese champions last December but seems completely unfazed by the sudden jump in level.

Usually lining up on the right or middle of Sporting's back three, the left-footed centre-back is generally the most proactive of the unit, often intercepting the ball high up the pitch before keeping it moving. Inacio is also progressive in his passing game -- he can hit an early ball in behind the defence to pinpoint a teammate -- and is exceptionally alert for a defender of his young age.

Central defender: Lisandro Martinez, 23, Ajax

With the 5-foot-10 Jurrien Timber alongside him, the 5-foot-9 Argentina international completes one of the shortest defensive partnership in the Champions League group stage. Even so, Martinez doesn't shy away from the aerial challenges coming his way and has come out on top from 70% of them this year as Ajax have impressed.

Martinez is an extremely difficult opponent to face. His high degree of alertness and mobility allows him to win the ball early and he masters the somewhat dying art of one-vs.-one defending in and around the penalty area. The left-footed defender is also tremendously safe and skilled in possession (95% pass accuracy) with one key pass on average per game.

Left-back: Morato, 20, Benfica

Strictly speaking the Brazilian has been fielded as a left centre-back in Benfica's back three this season, but is equally happy to explore space down the left flank. While Morato has only started two Champions League games, Jorge Jesus rated the ex-Sao Paulo man highly enough to start him against Bayern Munich, and he scored in the 5-2 defeat.

There are still aspects to improve in Morato's game: His passing is still relatively predictable -- typically looking to find wing-back Alex Grimaldo -- and he can sometimes look hesitant and slow on the turn. Yet he has shown himself to be physically strong, brilliant in the air, quick over longer distances and with a decent touch on the ball, so is clearly a player to watch.

Defensive midfielder: Mohamed Camara, 21, FC Salzburg

The Mali international has looked increasingly comfortable as the competition has developed. Camara plays with the presence, tactical discipline and confidence of a more seasoned defensive midfielder. While being safe, but not risk-averse, in possession, he is outstanding at the defensive side of the game. Indeed, he covers a lot of ground, features an impressive rate of interceptions and free ball pick-ups per match, while he often restrains himself from surging forward in order to cover for Salzburg's attack-minded full-backs. Already an undisputed regular in his first year, he's another product of the club's impressive setup.

Attacking midfielder: Christopher Nkunku, 24, RB Leipzig

One bright spot for RB Leipzig in a fairly miserable first part of the season has been the resurgence of Nkunku. Such has been his impact in the Champions League that he's reportedly attracted interest from the likes of Real Madrid and Liverpool. The versatile Frenchman -- who was never more than a squad player at Paris Saint-Germain before he left for Leipzig in 2019 -- made an early mark in the competition with a hat trick away against Manchester City (which featured two headed goals), then found the net against his former club, and twice vs. Club Brugge as well.

Nkunku is at his best when he can drift between the defensive lines in the final third and is exceptionally good at finding the right space and timing his runs into the box. Nkunku is a technically brilliant footballer who could well find himself at a bigger club in 2022.

Attacking midfielder: Pedro Goncalves, 23, Sporting

"Pote" was a sensation in last season's Portuguese league with 23 goals in 32 games, but he has also made his mark on the Champions League this season. The roaming attacking midfielder, whose real breakthrough in the Sporting first team came when Bruno Fernandes left for Manchester United in January 2020, mainly operates in the space behind the striker, and his knack for timing his runs into the box is nothing short of extraordinary (his second goal against Dortmund was one of the best of the competition so far). Always active and looking for room to exploit, Pote also has an excellent workrate.

Left winger: Arnaut Danjuma, 24, Villarreal

Within the space of a few months the Dutchman has removed any doubts over whether the move from the English Championship to Champions League was a leap too far. The €23.5m signing from Bournemouth has been one of the Europa League champions' top players this campaign, with his first half performance against Manchester United in September standing out.

Whether cutting in on his favoured right foot for an exquisite finish or finding space for a cross on the outside of the defender, Danjuma's quick body feints, changes of direction, instinctive flicks and lay-offs make him hard to stop.

Right winger: Antony, 21, Ajax

The progression displayed by the Brazilian over the past few months has been nothing short of phenomenal. Antony has used his lightning speed and one-vs.-one skills to devastating effect in the Champions League, running opposing full-backs ragged with his sprints and turns.

As well as being dangerous from long and mid-range, courtesy of his fine left foot, the newly capped Brazil international is also a great provider. His three assists for Sebastian Haller (five in total) -- which included a couple with the outside of his left foot -- were among the best in the tournament. Arguably one of the most entertaining individual players in European football right now, his defensive contribution is also developing fast.

Centre-forward: Darwin Nunez, 22, Benfica

Could Nunez eventually take over Uruguay's goal scoring mantle from Luis Suarez and Edinson Cavani? Based on his development over the past 12 months, the answer might well be yes.

Signed from Spanish side Almeria for €24m in January, he has kept on improving this season and has a number of bigger clubs taking note. With his great speed over long distances and balance, Nunez loves playing against a high defensive line and thrives when the game opens up to frequent transitions -- as it did when he helped to rip Barcelona to pieces.

His 6-foot-2 frame, brilliant heading technique and an ever-growing spatial awareness, means he's always a threat in the air. January may come too soon for a move, but don't rule out Nunez becoming a summer target for a host of European giants.