At 18 he signed for Pardaugava Riga moving on to Skonto Metāls and then into the Skonto first-team in 1995. He started playing as a midfielder, usually on the wings, before moving into a striker’s role.

His best goal ratio came in 1995 when he scored 8 in 9 games, which he followed up with 12 in 28 games the following season, as he became a regular in the Latvian national team. In his prime he was dubbed the “Latvian Michael Owen”.

Pahars broke into the Latvian national team at the start of 1996, and made his debut on 12 March 1996 in a 1–0 friendly defeat away to Cyprus. His first goal for his country came in his ninth match at home to Poland in a 3–2 defeat also in a friendly on 17 February 1997.

In the 1998 season he scored 19 goals in 26 games for Skonto, and his progress was attracting attention from bigger clubs; he had trials with Salernitana (Italy), Werder Bremen (Germany), and Casino Salzburg (Austria), but he was recommended to Southampton’s manager Dave Jones by Gary Johnson – the manager of the Latvian national team.

He had a trial in a reserve team match against Oxford United on 10 February 1999 in which he scored a perfect hat-trick – a header and a goal with each foot in a 7–1 victory.

Saints agreed a fee with Skonto of around £800,000 and despite difficulties in obtaining a work permit and objections from the PFA, these problems were overcome and he joined the Saints in March 1999, thus becoming the first Latvian to play in the FA Premier League.

He finally made his debut as a 70th-minute substitute away to Coventry City on 5 April 1999, with his home debut at The Dell coming on 17 April, when he came off the bench to score the crucial equaliser – and almost got a winner – against Blackburn Rovers in a 3–3 draw. At this time Saints were desperately trying to survive in the Premier League and had gone into the final game of the season needing a win to guarantee their place for a further season. Pahars scored twice in the 2–0 win over Everton at the Dell, thus securing Saints’ status in the Premiership for the following season.

After an indifferent start to the following season, he came off the bench to score the winner away to Bolton Wanderers on 15 September 2001. He scored at a regular rate over the next three months including the winner in a 1–0 victory over Charlton Athletic on 24 November – Saints first win in their new St Mary’s Stadium.

Despite Latvia not qualifying for the World Cup Finals they did have success in June 2001 when they beat Estonia and Lithuania, to lift the Baltic Cup, with Pahars scoring in both games. Pahars was then named Latvian Footballer of the Year for a third successive year in November 2001.

In the summer of 2002, Pahars required a hernia operation, which forced him to miss the whole of pre-season and although he scored a penalty in a 1–0 home win over Everton on 11 September he never fully recovered from his injury. His early season was rather stop-start and was not helped by the suspension for receiving a red card at home to Manchester City on 5 October. He then severely injured an ankle in November 2002, which kept him out for most of the rest of the season with another operation on the eve of the FA Cup Final to round off a miserable 2002–03 season.

The start to the 2003–04 season was again hampered by injury and comebacks for the reserves were ruined by injury recurrences. He did manage to play the closing minutes as Latvia claimed a place at Euro 2004. With that as an added incentive to get himself fully fit he found himself back in the Saints starting line up for 3 successive games which all ended in victories. His first goal of the season – and in more than a year – came at home to local rivals Portsmouth on 21 December 2003 in a 3–0 home win when he curled a superb right footer into the bottom right corner.

During a spell of injuries, he managed to play in the closing minutes as Latvia claimed a place in the European Championships in 2004 with a 2–2 draw in Turkey on 19 November 2003.

His 2005–06 season was another frustrating one with injury after injury again seeing his comebacks ruined. He did make 10 appearances during the season, scoring one goal, but it was not enough to save his Saints career, and, in May 2006, after seven years with 156 appearances and 45 goals for the club, it was announced that his contract with Southampton would not be renewed for the following season.

After the final game of the season, on 30 April 2006 Pahars took part in a ‘lap of appreciation’ by the Saints players around the St. Mary’s pitch, in an emotional goodbye for the player and many of the Southampton fans present.

In July 2006 Pahars signed with Anorthosis Famagusta, a Cypriot team managed by former Georgian International Temuri Ketsbaia.

On 2 September 2006, he returned to the Latvian national team for a match against Sweden. All in all, he played 75 times and scored 15 goals for Latvia.

His injury problems were frequent during his stay at the club, and, as a result, in January 2008, he was released.

In 2008, he joined his former home-land club Skonto, playing there for one season and helping the club reach good results in the national championship. After the season, he left Skonto FC, joining FK Jūrmala-VV finishing his career there with two games in the national championship.

In 2010 Pahars accepted an offer to become Aleksandrs Starkovs’ assistant at Skonto alongside legendary Vitālijs Astafjevs. He became the champion of Latvia in 2010 once again, this time in an assistant manager’s role.

In 2011 Starkovs left for FK Baku in Azerbaijan and Pahars became the manager of the club. Managing the club for two seasons, he helped the club win the Baltic League in 2011 and lift the Latvian Football Cup, as well as finish as the runners-up of the Latvian Higher League in 2012.

In December 2012, Pahars left Skonto, being succeeded by Tamaz Pertia.

Pahars accepted the opportunity to return to coaching, when the offer from LFF allowed him to become the manager of Latvian under-21 national team. Not long after his appointment, on 11 July 2013, Pahars was promoted, becoming the manager of the nation’s senior team, shortly after Aleksandrs Starkovs vacated his position.

Pahars was a candidate for Honoured to serve Riga in the 2020 Riga City Council election, but was not elected.