Rangers are expected to complete the deadline-day signing of Colombian winger Oscar Cortes on loan from Lens as they strive to bolster their attack for a cinch Premiership title assault. The 20-year-old – who made his international debut last year – arrived in Glasgow to seal a deal until the end of the season, with the Ibrox club having an option to buy at the end of the campaign. Gers boss Philippe Clement has already added Ivorian midfielder Mohamed Diomande on loan from Nordsjaelland and Portuguese attacker Fabio Silva on loan from Wolves this window as he bids to reel in Celtic at the top of the table. However, the Ibrox club – five points behind with a game in hand – look to have been thwarted in their bid to land Brazilian left-back Jefte from Fluminense. The Gers hoped to recruit the 20-year-old immediately, but he is currently on loan with APOEL Nicosia and the Cypriot club are reportedly intent on keeping him until the end of the campaign, so his proposed move to Scotland will have to wait until the summer. Across the city, Celtic are closing in on the loan signing of Norwich striker Adam Idah, with the 22-year-old Republic of Ireland international reportedly arriving in Glasgow on Wednesday to seal his move to the Hoops until the end of the season. Idah has scored 17 goals since graduating from the Canaries academy, with seven of them coming this season. The forward has won three senior international caps and is set to add to Brendan Rodgers’ options in the attacking department following the arrival of German winger Nicolas Kuhn from Rapid Vienna earlier in the window. The Celtic boss is also keen to add a left-back as Greg Taylor is facing a spell on the sidelines, with 31-year-old Paris St Germain player Layvin Kurzawa mooted as a possibility. Midfielder David Turnbull, who is out of contract at the end of the season, could be on his way out of Celtic Park amid strong interest from Cardiff, but Gustaf Lagerbielke is likely to be denied his move to Italian side Lecce as the Hoops are reluctant to sell the Swedish defender at a time when they have injury concerns over his fellow centre-back Cameron Carter-Vickers. Hearts forward Lawrence Shankland has been the subject of intense speculation in recent months, but the Jambos go into the final day of the window without any notable approaches having been made for their top scorer. The Edinburgh club have already bolstered their squad with the loan additions of Dexter Lembikisa and Scott Fraser, but it looks unlikely that they will secure Yan Dhanda before the deadline after the Ross County playmaker agreed a pre-contract to move to Tynecastle in the summer. Staggies boss Derek Adams said on Tuesday he expects the 25-year-old to remain in Dingwall for the rest of the season, while he hopes to add at least one and possibly two new players. Motherwell replenished their attack by signing 22-year-old Welsh forward Jack Vale on loan from Blackburn on Wednesday, while relegation rivals St Johnstone are hoping to land 25-year-old striker Adama Sidibeh from English non-league side Warrington Rylands. It remains to be seen how the sacking of manager Barry Robson on Wednesday impacts Aberdeen’s deadline-day plans, although they may feel compelled to add a centre-back after Slobodan Rubezic suffered a knee injury. Livingston boss David Martindale hopes to sign a new centre-back as well as Inverness midfielder David Carson, while Hibernian are another club in the market for a central defender.