In the UK Globe LTC showed support for young Alex and gave him a complimentary membership at the club and a few hours with a professional coach, he is now a life member.

Slabinsky made his ATP tour debut on 16 June 2008 when he played at the 2008 Nottingham Open against experienced American Vince Spadea but was beaten in straight sets 6–1, 7–5.

Slabinsky suffered a lacklustre season after that as he moved up onto the more difficult Challenger Circuits and failed to win a single title, but still managed to increase his ranking by 68 places.

Despite losing 3–6, 5–7, Slabinsky's rank increased to 331 the subsequent week, nine places from the entry list cut off for the Australian Open qualifying tournament.

He missed out on a place in the team after losing a 5 set match to Joshua Goodall, who later played as the British Number 1 singles player following the withdrawal of Andy Murray.

Slabinsky recorded his first singles win in a Grand Slam qualifying tournament by beating Adrian Cruciat of Romania 6–4, 6–3, before losing to Croatian Roko Karanušić in round two.

He underwent surgery which kept him out of the tour for three months, before returning to competitive tennis at the $15k Futures tournament held in Glasgow in October 2009.

At the $15k Cardiff Futures tournament, held a week later, Slabinsky was drawn against No.2 seed Uladzimir Ignatik of Belarus in the first round.

Following a 1–6, 2–6 defeat by Ignatik, Slabinsky focused on the doubles event, where he reached the final with partner Tim Bradshaw, finishing runner-up to the Irish pair of Barry King and James McGee following a 4–6, 6–7(3) loss.

[2] Slabinsky failed to get past the second round in the singles at his next three tournaments, the Dominican Republic Futures series, losing to American Adam El Mihdawy twice and Belgian Yannick Vandenbulcke once.

[6] Although Slabinsky was knocked out of the second round in the singles tournament at the $15k Brazil Futures held in Sorocaba, he did finish runner-up with Spaniard Guillermo Alcaide in doubles.

[7] At the 2011 Aegon International ATP Tour event, Alex qualified for the main draw by beating fellow Brits James Feaver (7–6(3), 6–1) and Sean Thornley (7–6(5), 6–3), followed by Russian Denis Matsukevich (6–1, 6–2, 7–6(4)), eventually narrowly losing to world top 20 ATP player Kevin Anderson (7–5, 6–4) in the Main Draw.