Complex sentence: He was dropped from the ODI squad because of poor form after The Ashes in 2005, but returned to the Australian squad in the 2006--07 Australian season after Simon Katich fell out of favour and Shane Watson was injured.
Split into simpler sentences: He was dropped from the ODI squad because of poor form after The Ashes in 2005, though he could not be kept away from the ODI squad for long. He returned to the Australian squad in the 2006--07 Australian season after Simon Katich fell out of favour and Shane Watson was injured.