Complex sentence: He immediately went into the first team and after a string of promising performances, he scored his first goal for Arsenal on 16 March 2013, opening the scoring in a 2--0 away victory against Swansea City.
Split into simpler sentences: He immediately went into the first team and after a string of promising performances. He scored his first goal for Arsenal on 16 March 2013, opening the scoring in a 2--0 away victory against Swansea City.