FOR a head coach at one of the most scrutinised clubs in the world, a strange anonymity surrounds Frank Rijkaard. He has led Barcelona for nearly five years, achieved their most important objectives - two league titles, one Champions League - but through it all he has preserved a remoteness that in critical times can work against him. And Barça are in a critical time. Should they not progress in the Champions League, where they meet Schalke 04 in the quarter-finals, he will probably be calling in the removal men this summer.

If he goes, it will be with dignity. Rijkaard does not bawl. Any rage boils over seldom and mostly in private. You have to go back to 1990 to find a public incident, when as a player he spat at his German opponent, Rudi Voller, during a World Cup finals match. In a long, decorated playing career, it is a struggle to find another instance when he behaved even rashly. In a management career that has taken in Holland, Sparta Rotterdam and Barça, the same applies. Those who laud Rijkaard tend to speak of him as a soother; those he frustrates accuse him of being insufficiently forthright or indecisive.

If he goes – and five years is a long spell for a modern manager of Barça – he will not go alone. The louder serenades around the exit door will accompany Ronaldinho and probably the midfielder Deco, two of the players whose gifts were once so thrillingly accommodated by Barcelona’s coaching staff and whose influence has waned as they remain second in La Liga. The failure to take advantage of the frequent slip-ups by league leaders Real Madrid has revealed a number of scapegoats, and Rijkaard’s name creeps higher and higher up the list. Some of the directors have become so disenchanted with his apparently easy-going manner that they have lobbied vigorously to replace him next season with a man of opposite character, Jose Mourinho (although Internazionale may well get the Portuguese first).

Mourinho is one of the few people to have visibly riled Rijkaard during his time at Barcelona, in the lead-up and controversial follow-ups to the meetings with Chelsea in the 2004-5 Champions League. Mourinho baited him, and briefly the Dutchman took the bait. Normally he treats provocation coolly, criticism with a thick skin.

For most of his time in Catalonia the attitude has served him well. “Coward” ran one of the headlines in a Barcelona newspaper the day after Rijkaard’s first gran clasico against Real had finished in a home league defeat for Barça for the first time in that fixture for 20 years.

He stuck it out. His first six months were troubled, but by the end of his second season, Barça had won their first Spanish championship since 1999; by the end of his third they had done the domestic league and Champions League double.

They did it stylishly, too. Ronaldinho flourished and creative players were accommodated in posts where a more conservative manager – a “coward” – might have put workmen. But even then, there was within Barcelona a reluctance to place the stamp of the coach on what had become the most watchable team in Europe.

The vice-president at the time of Rijkaard’s appointment, Sandro Rosell, remembers him being lukewarm about hiring Ronaldinho and uncertain about where to play him. Rossel claims it was more by accident than the coach’s design that the Brazilian emerged as the best footballer on earth, cutting on to his favoured right-foot from a position wide on the left of Barça’s 4-33.

Others are more generous about a coach, some of whose tinkerings have been iffy – a brief experiment with a back three – some very good. Under Rijkaard, Deco reinvented his game, operating deeper and with more defensive responsibility than he had at Porto under Mourinho. Transition made, Rijkaard was soon describing Deco as his team’s “barometer”: when he was good, so were Barça. For much of the past eight months, the converse applies. Deco can no longer claim confidently that he belongs in the first XI. Ronaldinho’s status has fallen even more dramatically and the club feels it can comfortably go into next season without him.

When, near the height of Barça’s success, Rijkaard dropped Ronaldinho and Deco for a big match, it was celebrated as evidence of his strength and wisdom. Now when he leaves out Ronaldinho, it is taken as proof that he can longer motivate a gifted individual.

Players describe his approach as amenable rather than confrontational. Comparing Rijkaard and Marcello Lippi, the coach of Italy’s World Cup-winning team, Barça’s Italian full-back, Gianluca Zambrotta, remarked: “They are very different. Rijkaard is much closer to the players.”

In an angry outburst, the striker Samuel Eto’o once accused Rijkaard of indulging Ronaldinho. This month there came from the captain, Carles Puyol, the puzzling suggestion that the media had influenced team selection. He was cross that the brilliant winger Lionel Messi had been rushed back too early after a period injured. Messi then picked up another injury. Barcelona hope that the Argentinian, the leading scorer in the Champions League, will be fit for the semi-finals, where, should they progress against Schalke, Barça would meet Manchester United or Roma.

Lagging in La Liga, Europe may represent Rijkaard’s salvation, or simply his best chance to leave on a high. In Europe, Barça have been more consistent than in domestic football, but then they have hardly been pressed: their opponents thus far have been Rangers, Celtic, Lyons and Stuttgart. Drawing Schalke, fifth in the Bundesliga yesterday morning, seemed to continue Barcelona’s good fortune. But elimination by Schalke would sentence their head coach.

Schalke 04 v Barcelona, Tuesday, ITV4, 7.30pm, kick-off 7.45pm