Any of their long-developed strategies to deal with the Abrams will make mincemeat of the stock Leopard 2A4s. The Abrams is still reasonably survivable against many of their recent updates, per most experts, but the unupgraded 2A4 is at a severe disadvantage.
Turkey may soon have cause to regret not buying the Trophy ADS system from Israel.
https://www.youtube.com/watch?v=OtMgnRMIspQ
Russia has a similar system installed on their tanks (having learned the need for them after Afghanistan and Chechnya) - Arena - and they may have even started installing the Ukranian-developed Zazlon system too.