2006–2009

As a youngster, Lagab took part in the Tour de l'Espoir, a stage race within his own country for young and talented riders. He finished in second place in the first stage of this race with the finish line in Bordj Bou Arreridj.^[3] It was the start of the career of a cyclist who would become one of the best cyclists in his country. The proof of that already came in the following year when he became second in the individual time trial of the Algerian national road cycling championships.^[4] Then in 2008 he went on to win two races in Tunisia, the Grand Prix de la ville de Tunis and the Grand Prix de la Banque de l'Habitat.^[5][6] Later on he improved his national time trial second place by winning the event in 2008.^[7] In addition he also became second in the road race at the same championships.^[8] This all resulted in his first contract with a UCI Continental team namely Doha Team for the 2009 cycling season.^[9] With this team, he took part in the Tour d'Alger in which he won the third stage, with start and departure in Alger as well as the general classification at the end.^[10][11] In another Algerian stage race, the Tour de Wilaya de Tipaza he finished in third place overall.^[12] Then in the Jelajah Malaysia he rode to a fifth place in the sixth stage, while he ended up in eighth position overall in the Tour of Singkarak.^[13][14] Team Doha then let him ride on the Presidential Tour of Iran where he took the seventh place overall.^[15] This year at the Algerian national road cycling championships he took a second place in the individual time trial.^[16] He then won the Grandglise criterium in Belgium before taking part at the 2009 Mediterranean Games in Pescara in which he placed 17th in the individual time trial and 19th in the road race.^[17][18][19] In the Tour des Aéroports in Tunisia he placed second in the first stage, before clinching the silver medal at the individual time trial of the 2009 Arab Cycling Championships.^[20][21] He finished 2009 with a third place in the Ouverture Saison de l'Algérie at the end of October.^[22]

2010

For the 2010 cycling season, the Doha Team did not return to the Continental circuit.^[23] As Lagab did not get a new contract with any other team he had to take a step back again. Still, 2010 turned out to be a good year for him in which he booked many successes. Already in January, he won a local Algerian race called Oued Al Alleug.^[24] In the Grand Prix International d'Alger he finished third in both the first and third stage and also reached the third spot in the general classification.^[25][26][27] Then in this year's Tour de Wilaya de Tipaza he won the first stage and finished third in the third stage.^[28][29] Lagab then traveled to Morocco to take part in the Challenges du Prince. He finished third in the Trophée Princier, second in the Trophée de l'Anniversaire, and fourth in the Trophée de la Maison Royale.^[30][31][32] Back in Algeria it was time for the national road cycling championships again. This time Lagab took the national title on the road race arriving first at the finish in Chlef.^[33] He went on to take part in the 2010 Arab Cycling Championships in Tunis where he took the silver medal in the individual time trial event.^[34] A bronze medal was added in the same discipline at the African Cycling Championships that were held in Kigali.^[35] There he also finished fourth in the team time trial (with Abdelmalek Madani and Hichem Chabane) and sixth in the road race.^[36][37]

2011

A newly set up UCI Continental Team in Algeria called Groupement Sportif Pétrolier Algérie contracted Lagab for the 2011 season, giving his career a new lift.^[38] It turned out to be the best year of his career until then and he became the best scoring rider on the team.^[39] It took however until April to book his first notable result with a second place in the Challenges Phosphatiers I (also named Challenge Khouribga).^[40] Approximately a month later his first win of the season was clinched as he took the first place in the Trophée Princier of the Challenges du Prince.^[41] In the Trophée Fédéral he won the first stage in Tiaret and became second in the second stage.^[42][43] This in combination with the results in the other stages gave him the win in the general classification as well.^[44] In Birtouta Lagab took the national title in the individual time trial championship, while he became second in the road race championship that was held in Ouled Fayet.^[45][46] A great achievement followed in the Tour d'Algerie where he won the second stage after finishing third in the first stage.^[47][48] He then received the leader's jersey after that stage and wore it for the remaining stages until he crossed the finish line of the fifth stage in Chrea to add another win to his palmares.^[49] This win was followed by another win in the Circuit d'Alger.^[50]

2011 continued with the 16th place in the Tour of Eritrea in preparation for the 2011 All-Africa Games that were held in Maputo.^[51] In the capital of Mozambique he finished in the fifth position of the road race, and he won the bronze medal at the individual time trial.^[52][53] His combined results of the year until then gave him an honorable third position in the 2011 UCI Africa Tour rankings.^[54] Lagab himself was not ready to finish 2011 yet and went on to win stage two and stage 5 of the Tour du Faso.^[55][56] Then in Eritrea he finished 4th in the team time trial of the 2011 African Cycling Championships alongside Abdelbasset Hannachi, Abderrahman Bourezza and Abdelmalek Madani.^[57] He also finished fourth in the individual time trial and 14th in the road race of the same Championships held in Asmara.^[58][59] After the Championships he won the Ouverture Saison de l'Algérie before heading to his next Championships, the 2011 Pan Arab Games in Doha.^[60] In the Qatari capital he won three medals for Algeria. A bronze medal in the individual time trial and team trial (with Abdalla Ben Youcef, Abdelmalek Madani and Abderrahman Bourezza), as well as the silver medal in the road race.^[61][62][63] Algeria ended up being the first country to arrive at the finish with three riders (the others being Abdelmalek Madani and Youcef Reguigui), which brought Lagab and his teammates the gold medal in the team road race event.^[64]

2012

In 2012 Lagab was still contracted to the Groupement Sportif Pétrolier Algérie team.^[65] He won the fifth stage of the Tour d'Algerie and got to the seventh position in the general classification.^[66][67] In the Tour du Maroc he finished in 14th position overall, while during La Tropicale Amissa Bongo he rode to a ninth position in the general classifications.^[68][69] At the second stage of the Tour of Eritrea he finished in third position.^[70] In June, he won another gold medal at the national road cycling championships, winning the individual time trial in Souk Ahras.^[71]