A reccuring theme on Borussia Dortmund's annual trips to 1. FSV Mainz 05 in recent years has been Jürgen Klopp's ongoing attachment to the club where he spent so long both as a player and coach.

That historical angle has been usurped this time around however and, rather than the BVB supremo's back story, much of the interest when the sides go head-to-head at the Coface Arena in Saturday's late kick-off (18:30 CEST) will be focused on a contest-within-a-contest starring the two Shinjis – frontman Okazaki of Mainz and Dortmund's prodigal son, Kagawa.

Record-breaker


Both players were among the top headline-makers on Matchday 3. Okazaki's 36th-minute opener away to Hertha Berlin was his 27th top-flight goal, putting him out on his own as the Bundesliga's all-time Japanese top scorer. The bustling 28-year-old forward netted again in added time to round out a 3-1 win in the capital, and pull further clear of Yasuhiko Okudera's previous 26-goal best-mark from almost 30 years ago.

While Okudera put in 234 appearances for 1. FC Köln, Werder Bremen and Hertha to attain that total, however, Okazaki overhauled him in his 99th Bundesliga outing. More to the point, as has been duly noted by the Dortmund defence, the 79-time Japan international has scored 18 times in just 36 games since moving to Mainz from Stuttgart, where he was generally deployed as a wide attacking midfielder.

Two impressive scoring ratios


Switched to his preferred position of centre forward by then-coach Thomas Tuchel at Mainz, he was in his element from the off and is evidently continuing to flourish under Tuchel's successor Kasper Hjulmand. Early days it may still be but Okazaki nonetheless goes into the meeting with Dortmund top of the individual scoring chart alongside Hertha's Julian Schieber on three goals – a total he is naturally keen to add to on the occasion of his 100th Bundesliga appearance.

His BVB namesake meanwhile has an even better goals-per-game ratio in Germany's top division and it was further improved when he got off the mark at the first time of asking, in his 'second debut' in yellow and black. Having run out to an ear-splitting reception at the Signal Iduna Park, Shinji Kagawa was soon helping his new-old team run the show against SC Freiburg and after paving the way for the opener with a typically incisive deep pass on the turn, the fans' favourite put Dortmund two up shortly before half time with a powerful finish of his own.

It all added up to an uncannily seamless re-transition for the 25-year-old attacking midfielder, who exploded on the Bundesliga scene after joining Borussia from Cerezo Osaka for a pittance and as a virtual unknown in the summer of 2010. An integral member of the side which won back-to-back league titles over the following two seasons, he took his leave of the German game in the same spectacular fashion as he had arrived, opening the scoring in a 5-2 rout of FC Bayern München that secured Dortmund the DFB Cup, and the domestic double, in May 2012.

Right man at the right time


After two years of decidedly mixed fortunes in England with Manchester United, the Kagawa show is now back in the Bundesliga. Shinji's first game of his second stint at BVB was also his 50th all-told in the league for Jürgen Klopp's side. His goal balance now stands at 22 – exceptional for a midfielder and, in half as many games, just six shy of compatriot Okazaki. Above and beyond his scoring exploits, however, Kagawa is a dynamic and versatile playmaker of the modern school and with Marco Reus, Jakub Blaszczykowski, Ilkay Gündogan and Nuri Sahin all currently unavailable in the engine room, his swift reintegration will be vital to Dortmund over the busy weeks ahead.

“He can play football, which is quite practical for our purposes,” Klopp noted laconically after the win against Freiburg. Next up is the trip to Mainz, familiar territory for the coach and with that fascinating subplot of a duel between Shinji and Shinji, the pick of a fine and steadily-growing crop of Japanese stars in the Bundesliga.