Braunschweig brilliant in the first half
Right from the get-go, the intensity was at an irresistible and high level. Both teams had early openings with plenty of early running made in the midfield. Artur Sobiech's early effort warmed the hands of Jasmin Fejzic, before the 'keeper clashed with Karaman. Thankfully, the situation was diffused quickly by Felix Zwayer.
As tempers flared, skill and technique came to the fore in the 17th minute. Reichel has a reputation for clean strikes and volleys especially, including against Fortuna Düsseldorf. This was closer to goal but more impressive, as a stunning bicycle kick sent the entire Eintracht-Stadion into wild celebration; it was just the start they wanted.
The battle for control left both wanting in a bid to get forward, as two strong midfields continue to butt heads. Perhaps unsurprisingly, it was another set-piece that proved the difference. It was only half cleared to Reichel, whose pass evaded everyone and found Hernandez. He rounded Philipp Tschauner and slotted home to make it 2-0.
But their joy would be short-lived and some immediate pressure from Hannover paid dividends. Felix Klaus' initial effort was well defended by Braunschweig but the dropping ball fell kindly for Harnik. He sent a volley at goal that struck the back of Saulo Decarli and looped over the stranded Fejzic to reduce the deficit and give Hannover hope.
Hannover complete their comeback
The second half brought a change for either side as Mirko Boland replaced Patrick Schönfeld and Miiko Albornoz took the place of Edgar Prib. Although any impact either would have was delayed when an incredibly long throw saw a flare land close to the centre circle. After a short delay, play quickly resumed.
It was just as lively in the second 45 as it was in the first, with neither team content to play the patient game; instead both went for the more attacking approach. Domi Kumbela had two chances in quick succession to put the game beyond doubt but he shot wide from Salim Khelifi's cut-back, before heading well wide moments later.
Their inability to put the game beyond doubt would be punished for the second time in as many weeks when Karaman struck in some style to beat Fejzic from the edge of the area. He picked the ball up and fired an arrowing effort into the top corner, levelling the game at 2-2 and suddenly the momentum had shifted firmly into Hannover's favour.
The final 20 minutes saw the visitors dominate and have what looked to be a stone-wall penalty claim turned down by Zwayer when the ball struck a stray Braunschweig arm. Fejzic then had to make two crucial saves late on as Harnik and Hannover just fell short of what would have been a memorable derby day victory.
It was a result that keeps Braunschweig top, now just a point clear of VfB Stuttgart. Hannover are just five points behind their local rivals in fourth.