Question: The 2015–16 season was the 89th season in ACF Fiorentina's history and their 78th in the top-flight of Italian football, the 2015–16 season was also notable for being the first season since the 2011–12 season in which the club manager was  replaced by which former Portuguese footballer, who played as a defensive midfielder, and a current coach?

Context paragraphs:
2016–17 ACF Fiorentina season: The 2016–17 season was the 90th season in ACF Fiorentina's history and their 79th in the top-flight of Italian football.  Fiorentina competed in Serie A, the Coppa Italia, and the UEFA Europa League.

List of Fiorentina Women's FC seasons: This is a list of seasons of Italian women's football team Fiorentina Women's FC, formerly known as ACF Firenze, which has been ACF Fiorentina's women's section since the 2015–16 season.

2011–12 ACF Fiorentina season: The 2011–12 season was the 85th season in ACF Fiorentina's history and the club's 74th season in the top-flight of Italian football.  Fiorentina competed in Serie A, finishing a disappointing 13th, and was eliminated in the round of 16 in the Coppa Italia.

Paulo Sousa: Paulo Manuel Carvalho de Sousa, (] ; born 30 August 1970) is a former Portuguese footballer who played as a defensive midfielder, and a current coach.

2017–18 ACF Fiorentina season: The 2017–18 season is the 91st season in ACF Fiorentina's history and their 80th in the top-flight of Italian football.  Fiorentina are competing in Serie A and the Coppa Italia, missing out on European football for the first time since the 2012–13 season following an eighth-place finish in the 2016–17 season.

Sandro Mencucci: Sandro Mencucci (Italian: [sandro meŋkuttʃi]; born 18 July 1961) is an Italian businessman and Executive Director Sports Area and Board Director of the Italian Serie A football club ACF Fiorentina based in Florence, Italy.  In 2007, Mencucci became the President of the Promesse Viola Srl, the official youth academy for the club.  In 2014, Mencucci, became the President of International Development Players LLC, a youth development academy under the guidance of the youth sector division of the club with its headquarters in the United States of America.  In 2015, Mencucci became President of the Fiorentina Women's Football Club, the first ever professionally-affiliated women's football club in the history of Italy.  In 2017, Fiorentina Women's Football Club won the 2016-2017 Italian Championship in only two years from its upstart.  This is the first Tricolore for ACF Fiorentina since May 6, 1969 and it is the first Serie A championship won by the ACF Fiorentina's current owner Andre Delle Valle.  The Fiorentina Women's FC qualified to participate in the UEFA Champion's League in the 2017-2018 season although they will have a UEFA ranking of 0.  On June 17, 2017, the club ACF Fiorentina won its first doublet since 1926 when the Fiorentina Women's FC won the Coppa Italia.

2010–11 ACF Fiorentina season: The 2010–11 season was ACF Fiorentina's 85th season in Italian football and their 73rd season in the first-tier, Serie A.  This was also the sixth consecutive season for the club in the top-level division of the Italian football league system.

2005–06 ACF Fiorentina season: The 2005–06 season was ACF Fiorentina's 80th season in its history and its 68th season in Serie A.  The club had its best season on the pitch since the 1998–99 season, originally finishing 4th with 74 points and securing a spot in the qualifying round of the 2006–07 UEFA Champions League.  However, the club was punished with a 30-point penalty for its involvement in the 2006 Italian football scandal, resulting in Fiorentina being pushed down the table to 9th.  This was a much better outcome than its original punishment, as "La Viola" were originally relegated to Serie B.  Following a successful appeal, Fiorentina was admitted to play in Serie A the following season, albeit losing its Champions League slot and having to start the season with a 15-point penalty, removing any chance of mounting a genuine title challenge and building on the success of the 2005–06 season.

2015–16 ACF Fiorentina season: The 2015–16 season was the 89th season in ACF Fiorentina's history and their 78th in the top-flight of Italian football.  Fiorentina finished the season in 5th place in Serie A, having topped the table early in the season.  In the Coppa Italia, the club was eliminated in the round of 16, losing at home to newly promoted Carpi 1–0.  Competing in the UEFA Europa League for the third season in a row, Fiorentina limped into second place in their group with a 3–1–2 record, and were eliminated in the Round of 32 by Tottenham Hotspur, 4–1 on aggregate.  The 2015–16 season was also notable for being the first season since the 2011–12 season in which the club was not managed by Vincenzo Montella, who had achieved 4th-place finishes in each of his seasons with the club.  Montella was replaced by Basel coach Paulo Sousa.

ACF Fiorentina: ACF Fiorentina S.p.A., commonly referred to as simply Fiorentina ] , is a professional Italian football club from Florence, Tuscany.  Founded by a merger in 1926, and refounded in 2002 following bankruptcy, Fiorentina have played at the top level of Italian football for the majority of their existence; only four clubs have played in more Serie A seasons.

Supporting paragraphs: 2015–16 ACF Fiorentina season Paulo Sousa
Answer: Paulo Sousa