The Thrawn Pincer was a space warfare tactic developed by Admiral Gial Ackbar shortly after Grand Admiral Thrawn's war on the New Republic. It was based on the Interdictor tactics brilliantly employed by the Grand Admiral to bring reinforcements into his attack on Coruscant and in other battles.
Grand Admiral Thrawn
It started with a main task force being divided into two. The first group would drop into an enemy system and engage the enemy fleet while the second would jump into a nearby system. When the enemy fleet activated its gravity well projectors, the commander would then order the second fleet to make a micro-jump through hyperspace, usually behind the enemy fleet. Ordinarily, a ship would come out of hyperspace without precise control of where it stopped, requiring it to continue traveling at sublight speeds to reach its intended destination. The advantage of this tactic, then, was that it permitted a fleet to come out of hyperspace at a precise, knowable position.
This tactic was notably used during the Battle of Ciutric that occurred in 9 ABY against Prince-Admiral Delak Krennel. It resulted in his death and the victory of New Republic forces.
Another form of this tactic was used during the Second Battle of Bilbringi, but it involved three fleets; one Imperial, led by Grand Admiral Gilad Pellaeon, and two of New Republic, led by Admiral Sien Sovv and General Wedge Antilles.