In 2001, aged 19, Saviola moved abroad to play for FC Barcelona in a PS15 million transfer. He obtained Spanish citizenship shortly after, thereby not being restricted by the Spanish league maximum on the number of non-European Union citizens allowed in each club. Under coach Carles Rexach, he scored 17 goals in his first season, finishing joint-fourth top scorer in La Liga.  Saviola's second year at the club did not start well, as he only scored two goals in the first half of the season. When Van Gaal was fired and Radomir Antic became the new Barcelona manager, he went on to net 11 goals in the latter half of the campaign; at the start of the following season Frank Rijkaard was appointed as new manager, and the player scored 14 times in the league alone, but was deemed surplus at the club as longtime offensive partner Patrick Kluivert.  Saviola was sent on loan in the summer of 2004, moving to AS Monaco FC in Ligue 1. As he did not fit into Rijkaard's plans he was again loaned out the following year, this time to Spanish club Sevilla FC, in order to replace Real Madrid-bound Julio Baptista; with his new club he won his first title in Europe, conquering the UEFA Cup -- he also scored nine times in the league, good enough for fifth.  Saviola returned to Barcelona for the 2006-07 season, playing in 18 league games, six as a starter, and netting five goals. He benefited greatly from injuries to teammates, most notably to Samuel Eto'o, and added five in as many matches in that season's Copa del Rey, notably a hat-trick against Deportivo Alaves (3-2 win at home, 5-2 aggregate).

Answer this question "who was his coach?" by extracting the answer from the text above.
Under coach Carles Rexach,