Tottenham are eyeing an ambitious move for €100 million-rated Bundesliga winger Yan Diomande as fan favourite Brennan Johnson is set to exit the club in the January transfer window. Johnson, who scored Spurs' historic winning goal against Manchester United in the Europa League final last season, has fallen out of favour under Thomas Frank and is now likely to leave the north London outfit.According to BBC Sport, Johnson, who ended Spurs' two-decade-long trophy drought last season with his strike in the Europa League final, is set to leave the club in the January transfer window. Tottenham have  agreed to sell the player to Crystal Palace for a reported transfer fee of £35 million ($47m/€40m). The decision is now up to the 24-year-old whether he wants to make the switch across London. Spurs are looking to add another forward to their ranks in January, which would push Johnson even further down the pecking order under Frank.The Guardian reported on Monday that Bournemouth are also keen on signing Johnson, as they see him as a potential replacement for Antoine Semenyo, who is on his way to join Manchester City. According to the BBC's reporting, Spurs are plotting an ambitious move to sign 19-year-old RB Leipzig winger Diomande to further bolster their attack in the upcoming window.However, as reported by The Athletic's Seb Stafford-Bloor, it is unlikely that the Bundesliga giants will agree to part ways with their star player midway through the season. The German club might consider opening transfer talks in the next summer transfer window, although they are likely to demand a whopping €100m (£86m/$117m) for the wonderkid. Spurs and Leipzig are also reported to be on good terms following previous negotiations for Timo Werner and Xavi Simons.Looking for smarter football bets? Get expert previews, data-driven predictions & winning insights with GOAL Tips on Telegram. Join our growing community now!Diomande arrived at RB Leipzig in July this year from Leganes and witnessed a rapid ascent that has justified Leipzig's significant initial investment and their subsequent bold valuation. Described as a "street footballer" who excels in one-on-one situations, the right-footed winger has electrified audiences with his direct running, dribbling ability, and powerful shot. After impressing throughout pre-season, he has seamlessly transitioned into the Bundesliga.Heading into the German winter break, Diomande has recorded seven goals and four assists in 16 games across all competitions for Leipzig.Add GOAL.com as a preferred source on Google to see more of our reportingFrank has found himself under immense pressure in his first season at Spurs, with the club currently on a worrying run of form which has conjured just two top-flight victories in their last nine fixtures.The former Brentford boss, who had earned goodwill while managing the Bees, has suddenly come under immense scrutiny and has even been told to resign from his role by former Spurs star Ramon Vega. After the club's narrow win over Palace last weekend, Vega wrote on social media: "Frank, stop talking about last season. They finished 17th. You now have more fit players than Ange had last season, yet you’re still not better off. In fact, it’s a shambles. At least Ange with no support made a miserable season into a wonderful ending for the fans by winning the European Cup and qualifying for the CL. You are now enjoying. So please do us a favour and resign, mate!"