[6] Before his transfer to Chelsea F.C., he acquired a Polish passport as well, on account of his Israeli-born mother who is of Ashkenazi Polish-Jewish and Latvian Jewish descent, that made him eligible to play as a non-foreigner in EU leagues including the UK.

[11] While he was promoted to the first team by manager Itzhak Shum, he did not feature in any matches, since his transfer was completed before the start of the 2006–07 season.

Sahar signed for Chelsea of the English Premier League in May 2006 from Hapoel Tel Aviv for £320,000,[13] having previously spent a two-month period on trial at Stamford Bridge.

Sahar was called up to the Chelsea first team to play Macclesfield Town in the FA Cup on 6 January 2007, and made his debut coming on as a substitute for Salomon Kalou in the 76th minute.

He made his Premiership debut on 13 January 2007, coming off the bench to replace Arjen Robben in the 82nd minute of the match against Wigan Athletic.

[14] He later made two additional Premier League substitute appearances for the Blues that season, against Manchester United and Everton.

Sahar joined then Championship side Queens Park Rangers, on loan, for the beginning of the 2007–08 season, on 26 July 2007, for an initial three-month period.

He followed this up with two goals in a pre-season friendly against Premier League side Fulham, earning Queens Park Rangers a 2–1 win.

[19] On 12 June 2008, it was reported that Sahar was in the Netherlands to discuss another season-long loan with Dutch club NEC Nijmegen.

[22] Sahar joined Premier League side Portsmouth on a six-month loan deal on 1 July 2008, and was given the number 26 shirt.

[23][24][25] He featured regularly in pre-season for Portsmouth, making seven appearances and scoring against Nigerian Premier League champions Kano Pillars, Conference South side Havant & Waterlooville, and Southern Football League Division One South & West side Gosport Borough.

This meant that they would have to participate in play-offs with teams from the Dutch second division in order to retain their place in the Eredivisie.

On 2 August 2009, Sahar scored two goals in a friendly match against Liverpool as a substitute, also picking up the man-of-the-match award in a 3–0 win.

[37] Despite the objections of his agent, Ronen Katzav, on 20 July 2010, Sahar joined his youth club Hapoel Tel Aviv on a one-year loan.

[38] When Itay Shechter went out with an injury midseason, Sahar capitalized on the increased playing time to create a striking partnership with Toto Tamuz.

Auxerre had an option to sign Sahar permanently for a fee of €1.5 million[39] which the club did not take advantage of at the end of the player's loan spell.

[41] On 21 July 2014, it was announced that Sahar had signed a one-year deal with an option for another year with Dutch Eredivisie side Willem II.

On 7 February 2007, at the age of 17-and-a-half, Sahar became the youngest player to ever play for the Israel national football team, in a friendly match against Ukraine (a feat since surpassed by Gai Assulin).