2009-10: Jonathan-Ismael Diaby played for the College Esther-Blondin Phenix in Quebec midget AAA hockey. He had 1 goal with 5 assists and 60 penalty minutes in 39 games. Diaby was drafted by Victoriaville in the fourth round (59th overall) of the 2010 QMJHL Entry Draft.
2010-11: Diaby played 19 regular season games and three playoff contests in the QMJHL for Victoriaville while playing for College Esther-Blondin in midget hockey. He had no points and was minus-one in 22 games for the Tigres. He scored 2 goals with 9 assists and had 79 penalty minutes in 20 games for the Phenix, which finished third in the CCM Division.
2011-12: Diaby skated in 51 games for Victoriaville as the Tigres finished with the QMJHL's third best record. He scored 1 goal with 8 assists and was plus-eight with 64 penalty minutes. The Tigres finished second in the East Division but were swept by Baie-Comeau in the first round of the playoffs. Diaby had no points and was minus-two with 11 penalty minutes in four playoff games.
2012-13: Diaby was the second-leading scorer amongst defensemen for Victoriaville in his second QMJHL season. He scored 4 goals with 22 assists and was plus-12 in 67 games and had 117 penalty minutes. The Tigres advanced to the second round of the playoffs after finishing fourth in the East Division and in nine playoff games Diaby was minus-two with 1 assist and 20 penalty minutes. He was ranked 37th amongst North American skaters in Central Scouting's final rankings prior to the 2013 NHL Draft.
First and foremost, there is his size. Diaby is blessed with great natural talents and is a punishing force on the blue line. Not only is he tall, but he has already filled out, which makes the lives of opposing players even more difficult as they try to enter into the offensive zone. He pairs that size with a nasty edge and good skating ability, allowing him to play a physical style without sacrificing positioning. He can make a solid first pass out of the zone, but his game is primarily defense-first.
Unfortunately, Diaby is going to be out for around six months with shoulder surgery, already limiting the action he will see in the season after his draft. He will likely miss about half the season, but despite the setback, Diaby has the makings of a very talented and hard to play against defenseman at full potential.