The young Bora-Hansgrohe sprinter, who also won the RideLondon-Surrey Classic in late July, took the bunch sprint in Brussels ahead of Trek-Segafredo's Jasper Stuyven on Saturday, and then beat Arnaud Démare (Groupama-FDJ) for victory at the GP de Fourmies in northern France on Sunday.
"I almost can't believe it," Ackermann said after taking the Fourmies win. "I'm just speechless. I knew that I was in good form, but I didn't expect to win two races on the same weekend. The guys did an excellent job and rode on the front of the peloton for such a long time. At the end of the day, we managed to pull off our plan perfectly, and I want to thank my teammates for their fantastic support."
The German's Bora-Hansgrohe team were similarly ecstatic with Ackermann's achievement.
"We're all very happy with today's win. In the history of the Brussels Cycling Classic and the GP de Fourmies, only one rider, Robbie McEwen, has managed to win both races," Bora sports director Christian Pömer pointed out, referencing the Australian's double in 2005.
"And now Pascal has also achieved that feat. This is a very impressive achievement. From the beginning of the race, the team took responsibility in the field and set the tempo.
"We didn't want to give the breakaway a significant advantage," continued Pömer. "Aleksejs Saramotins, Erik Baška, Peter Kennaugh and Juraj Sagan did a fantastic job and controlled the race very well. Our lead-out duo of Andreas Schillinger and Rudi Selig brought Pascal into a good position, from where he was able to launch his sprint at the ideal time. The team worked together extremely well and we can be very satisfied with today's win."
Saturday's finish at the Brussels Cycling Classic – a 'semi-Classic', and known as Paris-Brussels until five years ago – was marked by a crash that held up race favourite and defending champion Démare, while up at the front Ackermann overpowered Stuyven and Direct Energie's Thomas Boudat.
"I'm very happy to win here in Brussels, because it's my first victory on Belgian soil," Ackermann said after the first of his weekend wins. "I hope that I am able to achieve more success here in the future."
Although that second win wasn't in Belgium, it no doubt came much sooner than Ackermann or his team could have ever hoped.
With 2017 Fourmies winner Nacer Bouhanni (Cofidis) currently on duty at the Vuelta a Espana, the door was open for a new champion on Sunday, and Ackermann duly delivered in the bunch sprint, getting the better of Démare and Quick-Step's Alvaro Hodeg.
Ackermann has truly come of age in 2018. The 24-year-old joined Bora-Hansgrohe from German UCI Continental Team Rad-Net Rose in 2017, and after a fallow first season has scored eight victories in 2018.
Besides the RideLondon-Surrey Classic and his brace of wins at the weekend, Ackermann also won two stages of the Tour de Pologne in August, and a stage at both the Tour de Romandie and the Critérium du Dauphiné, with the latter coming just ahead of him becoming the German road race champion.