It's fair to say Gio Reyna will be glad to see the back of 2021/22, after injuries stalled a trajectory that had produced career-best numbers the previous campaign.
Reyna spent more time in the treatment room than on the pitch last season, hamstrung for 32 of Dortmund's 46 matches in all competitions. The 19-year-old attacker started BVB's opening five fixtures, but managed just eight more appearances before his season horribilis came to an abrupt end in early April.
"Gio will be a world-class player," Dortmund coach Marco Rose assured, speaking to bundesliga.com after Reyna limped off just two minutes into the 2-0 win at VfB Stuttgart on Matchday 29. "He's a top lad with unbelievable qualities. We'll help him to get properly back on his feet."
Watch: Gio Reyna - a season of setbacks
As much as he'd have liked, Rose won't be part of the recovery process. The Black-Yellows dismissed the ex-Borussia Mönchengladbach coach soon after the 2021/22 season finale, immediately reinstalling technical director Edin Terzic in his stead.
Terzic's appointment is likely to go down well in the dressing room following his successful, DFB Cup-winning stint at the helm in the latter part of 2020/21. Reyna, for one, is already a huge fan of the 39-year-old's style.
"Slowly, over time, I think he helped me build up my confidence again," the American recalled after Terzic helped him bounce back from the first form blip of his young career. "That was the most important thing for me - being with the team, knowing I should be on the pitch, playing games and scoring goals and getting assists."
Reyna was almost halfway into his first full season with the Dortmund pros, when Terzic was promoted from assistant to interim coach in place Lucien Favre on 13 December 2020. He'd featured prominently under Favre, earning his first-team stripes during the 2019/20 Rückrunde, making Bundesliga, UEFA Champions League, DFB Cup and USMNT history, and registering four goals and six assists in 23 appearances up until the 2020/21 winter break.
The son of former US international Claudio Reyna continued to enjoy regular minutes as Terzic attempted to make his mark, but the goals dried up. Seventeen matches, spanning mid-December 2020 through to mid-April 2021, came and went before he rediscovered his finishing touch in competitive club fare.
"Gio is still a teenager, so it's completely normal that there are phases where things don't always go to plan," Terzic remarked after Reyna broke the cycle with an assist in Stuttgart and a goal and assist against Werder Bremen the following week.
"We spoke to him a lot and tried to make some things clear. We made it clear that he has a clear role with us and always has our trust even if he doesn't start. What we worked really hard on was him regaining the courage to seek out one-on-one opportunities. That's what we've been lacking a bit in recent weeks and that's where he's taken a big step forwards.
"You just need to look at the way he powered through last week on the right wing [against Stuttgart], and set up a goal. He was involved again today and his goal was extraordinarily good. You can see his qualities, but he's also added tempo to his game. We've worked on that and we won’t stop working on it because that's exactly what we need him to do."
Watch: Gio Reyna's 2020/21 learning curve
Reyna concluded Terzic's temporary tenure on a run of six straight Bundesliga starts and with a further two goals to his name, after hitting a brace in the semi-finals of Dortmund's triumphant DFB Cup run. However, in a cruel twist of fate, recurring hamstring problems restricted him to just 13 outings, totalling two goals and as many assists, across the entire 2021/22 campaign.
"It is a frustrating injury for anyone because it's so unpredictable," explained Dr. Brian McDonough, discussing the impact of Reyna's hamstring injuries with State Of Soccer TV. "It happened three times and the recovery process is tough. It's a weakness for him, but it shouldn't be a crutch. The biggest thing he has going for him is that he's 19."
Reyna also has Terzic in his corner, a coach who understands the player and the person. Dortmund's new tactician faces a slightly different challenge compared to a year ago, but the tools and approach remain largely the same.
Winter World Cup or not, Terzic will only allow Reyna to run when he can walk. The rest - given the innate talents of the second youngest player in Bundesliga history to reach 50 appearances - will follow.
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