Marco Reus netted his 150th career Bundesliga goal, as Borussia Dortmund revived their title bid in style, producing an imperious display to ruthlessly thump six past Cologne at Signal Iduna Park.Dortmund had only lost once here against Cologne since April 1991, and they looked to get back to winning ways after last week’s Revierderby stalemate against Schalke. It was a spirited start for Die Schwarzgelben, and they set precedent for the game with a pair of unstoppable early goals. Having put his side ahead in the derby last weekend, Raphaël Guerreiro made the most of Donyell Malen’s irresistible skill, latching onto the Dutchman’s searching ball and poking a smart finish past Marvin Schwäbe.Before Cologne had a chance to catch their collective breaths, the lead was doubled. Jude Bellingham fed Marco Reus, who combined with Guerreiro and finally Sébastien Haller, who smashed into the top corner with Cologne defenders all at sea. A third soon followed as the BVB machine rumbled on. Malen’s shot was well saved by Schwäbe, but the attack was quickly recycled by Guerreiro, culminating in an emphatic curled shot from Reus finding the upper echelons of the black-and-yellow striped net.Malen was in the thick of the first-half action, and he took matters into his own hands as he blasted in a fourth which was too hot to handle for the Cologne goalkeeper. With a rout on the cards and the Billy Goats goalless in over a month, Davie Selke stepped in to at least give the fans in the Gästeblock something to celebrate. His initial strike was parried by Meyer, but a second bite at the cherry ensured the scoreline read 4-1 at the break.The home side had clearly been instructed to apply more caution by Edin Terzić at halftime, and the second period began in a more subdued manner. The tactical change put Dortmund in assured control of the game and the famous ‘Gelbe Wand’ were soon treated to more. Mahmoud Dahoud’s whipped free kick curled against the crossbar and fell kindly for Haller, whose second was a considerably easier finish than the first. Die Borussen had developed a penchant for quick-fire doubles, and another was in the offing, as Malen fought off Eric Martel and played through Reus. As he has done throughout his glittering career, the captain finished emphatically for the landmark tally.A frantic spell at the end of the game resulted in both sides hitting the woodwork within 30 seconds, but Dortmund cruised to the 6-1 victory, and in doing so made a big statement to Bayern Munich as to their intentions in what is shaping up to be a heated title race.BUNDESLIGA – ROUND 25FridayBorussia Monchengladbach – Werder 2-2 (0-0)/Thuram 48, Neuhaus 73 – Ducksch 65, 89/SaturdayAugsburg – Schalke 1-1 (0-0)/Maier 51 – Bulter 90+3 pen/Stuttgart – Wolfsburg 0-1 (0-0)/Marmousch 56/Bochum – RB Leipzig 1-0 (0-0)/Masovic 48/Hoffenheim – Hertha 3-1 (2-0)/Kramaric 24 pen, 37 pen, Bebou 51 – Jovetic 90+2/Dortmund – Koln 6-1 (4-1)/Guerreiro 15, Haller 17, 69, Reus 32, 70, Malen 36 – Selke 42/Sunday17:30: (2.45) Union Berlin (3.15) Eintr.Frankfurt (3.30)19:30: (5.40) Leverkusen (4.00) Bayern (1.62)21:30: (2.25) Mainz (3.45) Freiburg (3.40)***odds are subject to change***