Due to long-term injuries to Mark Viduka and Alan Smith, as well as shorter term injuries to Michael Owen and Obafemi Martins, Ameobi was able to start the 2008–09 season in the first team squad. He managed to score his first goal in two years for Newcastle in a 2–2 home draw with Manchester City on 20 October. After the match, interim manager Joe Kinnear praised Ameobi and backed him to kick-start his career. He followed this up with a goal in his next game away to Sunderland in a 2–1 defeat on 25 October. He signed a new deal with the club in January 2009 to keep him contracted until 2012.
He scored a penalty to mark his 50th goal for Newcastle on 1 February 2009 against local rivals Sunderland to make the final score 1–1. He scored his first ever career hat-trick in Newcastle's first home match in the Championship against Reading on 15 August. The first two goals were diving headers, and he completed his hat-trick with a penalty, which he placed in the bottom left corner, sending the keeper the wrong way. He scored in the next game in a 1–0 victory over Sheffield Wednesday taking his tally to four goals in three games, equalling his total for the previous season. Following these early season performances he was named the Championship player of the month for August.
In late 2009, Ameobi declared his interest in playing for Nigeria. On 14 January 2011, he was announced in the Nigerian national squad for the first time, for a friendly against Guatemala in the United States, in February. He withdrew from the replacement game against Sierra Leone after breaking his cheekbone in a Premier League match.