Leicester City Wesolowski played for Australian side
Northern Spirit before signing for
Leicester City in 2002. After showing a lot of potential in the reserves, Wesolowski played for Leicester in a pre-season friendly against
Celtic in 2005, but suffered a broken leg due to a challenge from
Bobo Baldé. He underwent surgery on the leg but the injury sidelined him until the start of 2006. Wesolowski returned and impressed for the Leicester first team, making his debut at home to
Cardiff City in January 2006. However, after only five appearances, he broke his same leg against Brighton in February. The departure of
Joey Guðjónsson gave Wesolowski the opportunity to become a first team regular, although he still faced stiff competition from teammates
Stephen Hughes and
Andy Johnson for the central midfield spot. He scored his first senior goal in a 4–3
FA Cup defeat to
Fulham on 17 January 2007. In July 2007, Wesolowski agreed to a contract extension with Leicester that would see him remain at the club until 2011. He scored his second goal of his career in a 1–0
League Cup win over
Accrington Stanley on 14 August 2007, before being sidelined for six weeks with a hamstring injury on 18 September in a 3–2 League Cup win over
Nottingham Forest. Wesolowski had more hamstring problems following recovery, and he was injured again on 8 December in a 2–1 defeat to
West Brom, sidelining him until Christmas. Wesolowski lost his place in the first team the following season, playing just four cup matches. On 2 October 2008, he joined
Cheltenham Town on a three-month loan deal, linking up with former Leicester manager
Martin Allen and fellow loanee
Barry Hayles, with the option of being recalled after the first month. His loan ended early after suffering a fractured ankle in a 2–0 away defeat to
Tranmere Rovers in October. On 2 February 2009, Wesolowski joined
Dundee United on loan for the remainder of the 2008–09 season, with the option of making the deal permanent. He made his debut in a 1–0 home defeat to
Hearts, playing for 65 minutes before being substituted. On 4 August 2009, Wesolowski joined
SPL side
Hamilton Academical on loan for an initial six-month period, which was extended till the end of the season after some impressive run of form.
Peterborough United On 1 June 2010, Wesolowski signed a two-year deal at
Peterborough United for an undisclosed sum.
Oldham Athletic On 8 August 2011, Wesolowski signed a one-year deal with league one club
Oldham Athletic. Wesolowski had his best season for the club yet in the 2013–14 season, he played nearly every game for the club & scored 5 goals, his best ever goal – scoring season. The vast improvement he had shown resulted in him scooping up 5 awards at the end of season awards, including Player of the Year. On 7 May, when the clubs retained list was announced, it was confirmed that a formal contract offer had been made to Wesolowski. With Wesolowski stating that he "would love to stay here" and that he would like to come to an arrangement with the club over a new contract.
Shrewsbury Town On 6 June 2014, despite a contract offer from Oldham, Wesolowski moved to
Shrewsbury Town in
League Two on a free transfer. He made his debut on the opening day of the season, coming on as a substitute in a 2–2 draw away at
A.F.C. Wimbledon, and was a regular in the first team squad until suffering a season-ending injury in a home match against
Hartlepool United on 17 January 2015 where he ruptured two knee ligaments. He scored his first and what turned out to be only goal for Shrewsbury in a 2–1 win over
Portsmouth on 25 October 2014. After playing a full ninety minutes and scoring Shrewsbury's equalising goal in their
Shropshire Senior Cup final win against local rivals
AFC Telford United, he returned to the first team ahead of schedule in a home match against
Sheffield United in April 2016. At the end of the season, Wesolowski was offered a new contract – reportedly on reduced terms – and was still training with the first-team during the following pre-season. He was later reported to be training with
National League side
Lincoln City, but was unable to agree to a contract.
Guiseley Wesolowski joined
National League club
Guiseley in October 2016. ==International career==