Every team has one. They don't hog the limelight, grab the headlines or often get picked by fantasy football managers, but they are among the first names on the teamsheets of the men who plot the course of clubs in the Bundesliga.
bundesliga.com raises its voice to speak up for the unsung heroes who have shone for their sides this season.
Jiri Pavlenka(Werder Bremen)
Clean sheets: 7
There is probably a sign in the dressing room at the Weser Stadium that reads, 'You don't have to be mad to be a goalkeeper to play here, but it helps'. Maybe that is why a budding, brilliant goalkeeper called Petr Cech did not join the club when he went to northern Germany for a trial in 2001.
Bremen's reputation as a side where the best form of defence is attack, attack, attack did not deter Pavlenka last summer — "I must have thought about it for all of five seconds," was how he described mulling over the club's offer — and Werder fans must be ever so thankful.
The former Slavia Prague man, who studiously analyses each of his performances, shares the same hulking 6'4" build as Cech, and also — fortunately for Bremen — his great goalkeeping compatriot's ability to keep a clean sheet that must be the envy of the world's five-star hotels.
Watch: Jiri Pavlenka against the world!
Usually strikers' goals keep sides up, but Bremen have only the 11th-best attack in the Bundesliga compared to the sixth-best defence. Pavlenka's 77 per cent saves-to-shots ratio is the Bundesliga's best, which says it all.
Whether Werder play another top-flight season is — almost literally — in the hands of Pavlenka. "I'm not sure he knows how good he is," said Bremen coach Florian Kohfeldt. Maybe he doesn't, but we do.
Position: Attacking midfielder
While their young Austrian forward might struggle to switch off sometimes, Augsburg fans can rest easy in the closing stages of the season thanks to Gregoritsch's contribution to ensuring they will spend another term in the playground of German football's biggest boys.
They may even argue they would have had ambitions beyond a comfortable mid-table finish had Gregoritsch been able to sustain his stunning Hinrunde form in which he netted eight times to put Manuel Baum's unheralded squad in the hunt for a European place next season.
That they have dropped out of the running can be — in large part — put down to Gregoritsch's dip in form. Just three goals have come in the second half of the season for the Austria international, but with a career-best total of 11 married to two assists, he has still had a hand in more than one-third of his club's top-flight strikes this season.
His imposing 6'3" frame has given Augsburg presence at both ends of the pitch, and he has won over half of his aerial challenges, evidence of his greater determination to help out without — as well as with — the ball.
"His work when we don't have possession is much more pronounced, the intensity is more pronounced," Baum explained. "What he can do on the ball, we all know. What he can do without, perhaps he himself didn't know until now."
You wonder whether Caligiuri would make a splash when he dives into a swimming pool as the hard-working midfielder never makes waves. That is, no doubt, one of the reasons why the down-to-Earth folk of the blue side of the Ruhr Valley have taken to him. The main one, though, is that he gives everything to their cause.
"He always wants to win, even in training," says coach Domenico Tedesco. "He's immensely important for our team," chimes in sporting director Christian Heidel, who had already tried to sign Caligiuri when plotting strategy at Mainz before finally pinning his man down in January 2017. "What he covers in kilometres, how many challenges he wins, it's unbelieveable. And added to that, he's technically good."
He may not be quite as sharp on the ball as Kevin De Bruyne, in whose shadow he — and everyone else, for that matter — stood while at Wolfsburg, but Caligiuri has enough ability to have impressed Chelsea boss Antonio Conte, who called up the German-born purveyor of guile and graft while he was Italy coach.
Watch: Caligiuri's incredible solo goal against Mainz!
Tedesco is a fan of those same qualities. He has made Caligiuri a cornerstone of the Royal Blues' season — only Ralf Fährmann and Naldo have more Bundesliga appearances this term — and has been richly rewarded.
Decisive goals in wins over Mainz, Augsburg and Freiburg have brought nine points, while his second-half penalty against Freiburg — his former club must be sick of the sight of him! — kickstarted the 2-0 win on Matchday 28 that keeps Schalke on course for second place.
But it is his performance at Leverkusen on Matchday 24 that best sums up this very definition of a team player.
After laying on a goal — his sixth assist of the season, a career-best — Caligiuri was in pole position to take the penalty awarded to his side. Instead, he allowed the freshly recalled Nabil Bentaleb to shoot from the spot — and score — to boost the Algeria international's confidence. Classy, and typical Caligiuri
Yussuf Poulsen(RB Leipzig)
Poulsen is the ultimate Marmite footballer: you either love him, or you hate him.
His own team-mates and Leipzig fans belong to the first group, everyone who has to face the Denmark international forward is in the latter camp. That's because Poulsen is an absolute terror to play against, a Viking warrior who could only more closely resemble one of his country's famous, feared invaders were he to step onto the pitch with a horned helmet.
He makes the most challenges of any Leipzig player — on average 37 per game — and wins 48 per cent of them while racing through nearly 7.5 miles every 90 minutes. Any industrious midfielder would be happy with those stats, nevermind a striker! His unselfishness has drawn criticism due to his modest goals tally — he has four in the league this season — but those who play alongside him or pick him recognise the contribution he makes to his team's strikes even without hitting the net himself.
"Yussuf is a great team player, that is above all his strength," said RBL coach Ralph Hasenhüttl of a player who is his club's Emile Heskey to Timo Werner's Michael Owen. "He's always looking for his team-mates."
Take the 3-1 win over Napoli in the UEFA Europa League, it was a Poulsen masterclass.
After intelligently letting the ball run through his legs to allow Werner to equalise, he then — when one-on-one with the hosts' former Bayern goalkeeper Pepe Reina — slipped the ball sideways for Bruma to net the second when he could have gone for goal himself.
"As far as I'm concerned, it's not about me absolutely having to score goals myself," Poulsen, who is now in his fifth year with last season's Bundesliga runners-up. "When I can set up a team-mate, it makes no difference."
Niklas Süle(Bayern Munich)
Pass completion: 94 per cent
Duels won: 63 per cent
"The way they approach training; the way they eat – it’s all something I can learn from," he explained. "I chose to come here so I could play alongside the two best defenders in the world."
While everyone thought the hulking 6'5" centre-back would be schooled mostly in training, his route along the learning curve has actually been even steeper still. Injuries to his vaunted team-mates mean Süle has made just one Bundesliga appearance fewer than Hummels, and four more than Boateng this season.
Though he had amassed more than 100 league games for Hoffenheim, the 22-year-old was a novice at European level, but did not look like one as he started five of Bayern's six UEFA Champions League group stage games. Domestically and internationally, Süle has slotted in for one of his fellow centre-backs, and the heart of the Bayern back four has remained just as strong.
When you look at Süle's fairytale numbers, you see why: 63 per cent of challenges won, 12 goals conceded in 21 league games. But he has not simply thrown the weight of his hefty 220-pound frame around to get them. There is far more silk than steel in Süle, who has committed just ten fouls, completed all but six per cent of his passes, and who can propel his juggernaut build at nearly 21 miles per hour. Yes, wow!
Earlier this season, Süle had stated that Boateng in particular had been a role model of his, adding: "I'dnever put myself on the same level as him." If he keeps playing like this he won't need to. Others will do it for him.